diff --git a/NEWS.md b/NEWS.md
index 036712a3..c55c7e0d 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -6,7 +6,7 @@
 
 - Improved: Better documentation about `-j`, with stronger recommendations not to set it too high.
 
-- Mutate `+, -, *, /, %` binary ops.
+- New: Mutate `+, -, *, /, %, &, ^, |, <<, >>` binary ops, and their corresponding assignment ops like `+=`.
 
 ## 23.12.1
 
diff --git a/src/mutate.rs b/src/mutate.rs
index 25ebb7b2..a3fc32e1 100644
--- a/src/mutate.rs
+++ b/src/mutate.rs
@@ -250,7 +250,7 @@ mod test {
         let mutants = workspace
             .mutants(&PackageFilter::All, &options, &Console::new())
             .unwrap();
-        assert_eq!(mutants.len(), 3);
+        assert_eq!(mutants.len(), 5);
         assert_eq!(
             format!("{:#?}", mutants[0]),
             indoc! {
@@ -332,7 +332,7 @@ mod test {
             &Options::default(),
             &Console::new(),
         )?;
-        assert_eq!(mutants.len(), 3);
+        assert_eq!(mutants.len(), 5);
 
         let mutated_code = mutants[0].mutated_code();
         assert_eq!(mutants[0].function.as_ref().unwrap().function_name, "main");
diff --git a/src/snapshots/cargo_mutants__visit__test__expected_mutants_for_own_source_tree.snap b/src/snapshots/cargo_mutants__visit__test__expected_mutants_for_own_source_tree.snap
index 15e2451d..ae85c470 100644
--- a/src/snapshots/cargo_mutants__visit__test__expected_mutants_for_own_source_tree.snap
+++ b/src/snapshots/cargo_mutants__visit__test__expected_mutants_for_own_source_tree.snap
@@ -33,6 +33,20 @@ src/console.rs: replace Console::walk_tree_done with ()
 src/console.rs: replace Console::scenario_started -> Result<()> with Ok(())
 src/console.rs: replace Console::scenario_started -> Result<()> with Err(::anyhow::anyhow!("mutated!"))
 src/console.rs: replace Console::scenario_finished with ()
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
+src/console.rs: replace += with -= in Console::scenario_finished
+src/console.rs: replace += with *= in Console::scenario_finished
 src/console.rs: replace || with && in Console::scenario_finished
 src/console.rs: replace || with == in Console::scenario_finished
 src/console.rs: replace || with != in Console::scenario_finished
@@ -78,6 +92,8 @@ src/console.rs: replace <impl Write for DebugLogWriter>::flush -> io::Result<()>
 src/console.rs: replace <impl Write for DebugLogWriter>::flush -> io::Result<()> with Err(::anyhow::anyhow!("mutated!"))
 src/console.rs: replace <impl Model for LabModel>::render -> String with String::new()
 src/console.rs: replace <impl Model for LabModel>::render -> String with "xyzzy".into()
+src/console.rs: replace += with -= in <impl Model for LabModel>::render
+src/console.rs: replace += with *= in <impl Model for LabModel>::render
 src/console.rs: replace > with == in <impl Model for LabModel>::render
 src/console.rs: replace > with < in <impl Model for LabModel>::render
 src/console.rs: replace > with == in <impl Model for LabModel>::render
@@ -146,6 +162,10 @@ src/console.rs: replace plural -> String with "xyzzy".into()
 src/console.rs: replace == with != in plural
 src/copy_tree.rs: replace copy_tree -> Result<TempDir> with Ok(Default::default())
 src/copy_tree.rs: replace copy_tree -> Result<TempDir> with Err(::anyhow::anyhow!("mutated!"))
+src/copy_tree.rs: replace += with -= in copy_tree
+src/copy_tree.rs: replace += with *= in copy_tree
+src/copy_tree.rs: replace += with -= in copy_tree
+src/copy_tree.rs: replace += with *= in copy_tree
 src/copy_tree.rs: replace copy_symlink -> Result<()> with Ok(())
 src/copy_tree.rs: replace copy_symlink -> Result<()> with Err(::anyhow::anyhow!("mutated!"))
 src/fnvalue.rs: replace return_type_replacements -> Vec<TokenStream> with vec![]
@@ -202,8 +222,12 @@ src/in_diff.rs: replace strip_patch_path -> &Utf8Path with &Default::default()
 src/in_diff.rs: replace affected_lines -> Vec<usize> with vec![]
 src/in_diff.rs: replace affected_lines -> Vec<usize> with vec![0]
 src/in_diff.rs: replace affected_lines -> Vec<usize> with vec![1]
+src/in_diff.rs: replace += with -= in affected_lines
+src/in_diff.rs: replace += with *= in affected_lines
 src/in_diff.rs: replace < with == in affected_lines
 src/in_diff.rs: replace < with > in affected_lines
+src/in_diff.rs: replace += with -= in affected_lines
+src/in_diff.rs: replace += with *= in affected_lines
 src/in_diff.rs: replace && with || in affected_lines
 src/in_diff.rs: replace && with == in affected_lines
 src/in_diff.rs: replace && with != in affected_lines
@@ -220,6 +244,8 @@ src/in_diff.rs: replace partial_new_file -> Vec<(usize, &'d str)> with vec![(0,
 src/in_diff.rs: replace partial_new_file -> Vec<(usize, &'d str)> with vec![(0, "xyzzy")]
 src/in_diff.rs: replace partial_new_file -> Vec<(usize, &'d str)> with vec![(1, "")]
 src/in_diff.rs: replace partial_new_file -> Vec<(usize, &'d str)> with vec![(1, "xyzzy")]
+src/in_diff.rs: replace += with -= in partial_new_file
+src/in_diff.rs: replace += with *= in partial_new_file
 src/interrupt.rs: replace install_handler with ()
 src/lab.rs: replace test_mutants -> Result<LabOutcome> with Ok(Default::default())
 src/lab.rs: replace test_mutants -> Result<LabOutcome> with Err(::anyhow::anyhow!("mutated!"))
@@ -334,6 +360,20 @@ src/outcome.rs: replace Phase::name -> &'static str with "xyzzy"
 src/outcome.rs: replace <impl Display for Phase>::fmt -> fmt::Result with Ok(Default::default())
 src/outcome.rs: replace <impl Display for Phase>::fmt -> fmt::Result with Err(::anyhow::anyhow!("mutated!"))
 src/outcome.rs: replace LabOutcome::add with ()
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
+src/outcome.rs: replace += with -= in LabOutcome::add
+src/outcome.rs: replace += with *= in LabOutcome::add
 src/outcome.rs: replace LabOutcome::exit_code -> i32 with 0
 src/outcome.rs: replace LabOutcome::exit_code -> i32 with 1
 src/outcome.rs: replace LabOutcome::exit_code -> i32 with -1
@@ -427,7 +467,11 @@ src/path.rs: replace ascent -> isize with 0
 src/path.rs: replace ascent -> isize with 1
 src/path.rs: replace ascent -> isize with -1
 src/path.rs: replace == with != in ascent
+src/path.rs: replace += with -= in ascent
+src/path.rs: replace += with *= in ascent
 src/path.rs: replace != with == in ascent
+src/path.rs: replace -= with += in ascent
+src/path.rs: replace -= with /= in ascent
 src/path.rs: replace > with == in ascent
 src/path.rs: replace > with < in ascent
 src/path.rs: replace <impl Utf8PathSlashes for Utf8Path>::to_slash_path -> String with String::new()
@@ -453,6 +497,8 @@ src/pretty.rs: replace == with != in <impl ToPrettyString for T>::to_pretty_stri
 src/pretty.rs: replace || with && in <impl ToPrettyString for T>::to_pretty_string
 src/pretty.rs: replace || with == in <impl ToPrettyString for T>::to_pretty_string
 src/pretty.rs: replace || with != in <impl ToPrettyString for T>::to_pretty_string
+src/pretty.rs: replace += with -= in <impl ToPrettyString for T>::to_pretty_string
+src/pretty.rs: replace += with *= in <impl ToPrettyString for T>::to_pretty_string
 src/process.rs: replace Process::run -> Result<ProcessStatus> with Ok(Default::default())
 src/process.rs: replace Process::run -> Result<ProcessStatus> with Err(::anyhow::anyhow!("mutated!"))
 src/process.rs: replace Process::start -> Result<Process> with Ok(Default::default())
@@ -523,9 +569,13 @@ src/span.rs: replace == with != in Span::extract
 src/span.rs: replace < with == in Span::extract
 src/span.rs: replace < with > in Span::extract
 src/span.rs: replace == with != in Span::extract
+src/span.rs: replace += with -= in Span::extract
+src/span.rs: replace += with *= in Span::extract
 src/span.rs: replace > with == in Span::extract
 src/span.rs: replace > with < in Span::extract
 src/span.rs: replace == with != in Span::extract
+src/span.rs: replace += with -= in Span::extract
+src/span.rs: replace += with *= in Span::extract
 src/span.rs: replace && with || in Span::extract
 src/span.rs: replace && with == in Span::extract
 src/span.rs: replace && with != in Span::extract
@@ -565,7 +615,11 @@ src/span.rs: replace && with != in Span::replace
 src/span.rs: replace == with != in Span::replace
 src/span.rs: replace >= with < in Span::replace
 src/span.rs: replace == with != in Span::replace
+src/span.rs: replace += with -= in Span::replace
+src/span.rs: replace += with *= in Span::replace
 src/span.rs: replace == with != in Span::replace
+src/span.rs: replace += with -= in Span::replace
+src/span.rs: replace += with *= in Span::replace
 src/span.rs: replace && with || in Span::replace
 src/span.rs: replace && with == in Span::replace
 src/span.rs: replace && with != in Span::replace
diff --git a/src/visit.rs b/src/visit.rs
index 524febcf..7cffa92b 100644
--- a/src/visit.rs
+++ b/src/visit.rs
@@ -9,6 +9,7 @@
 
 use std::collections::VecDeque;
 use std::sync::Arc;
+use std::vec;
 
 use anyhow::Context;
 use proc_macro2::{Ident, TokenStream};
@@ -368,15 +369,25 @@ impl<'ast> Visit<'ast> for DiscoveryVisitor<'_> {
             BinOp::Le(_) => vec![quote! {>}],
             BinOp::Ge(_) => vec![quote! {<}],
             BinOp::Add(_) => vec![quote! {-}, quote! {*}],
+            BinOp::AddAssign(_) => vec![quote! {-=}, quote! {*=}],
             BinOp::Sub(_) => vec![quote! {+}, quote! {/}],
+            BinOp::SubAssign(_) => vec![quote! {+=}, quote! {/=}],
             BinOp::Mul(_) => vec![quote! {+}, quote! {/}],
+            BinOp::MulAssign(_) => vec![quote! {+=}, quote! {/=}],
             BinOp::Div(_) => vec![quote! {%}, quote! {*}],
+            BinOp::DivAssign(_) => vec![quote! {%=}, quote! {*=}],
             BinOp::Rem(_) => vec![quote! {/}, quote! {+}],
+            BinOp::RemAssign(_) => vec![quote! {/=}, quote! {+=}],
             BinOp::Shl(_) => vec![quote! {>>}],
+            BinOp::ShlAssign(_) => vec![quote! {>>=}],
             BinOp::Shr(_) => vec![quote! {<<}],
+            BinOp::ShrAssign(_) => vec![quote! {<<=}],
             BinOp::BitAnd(_) => vec![quote! {|}, quote! {^}],
+            BinOp::BitAndAssign(_) => vec![quote! {|=}, quote! {^=}],
             BinOp::BitOr(_) => vec![quote! {&}, quote! {^}],
+            BinOp::BitOrAssign(_) => vec![quote! {&=}, quote! {^=}],
             BinOp::BitXor(_) => vec![quote! {|}, quote! {&}],
+            BinOp::BitXorAssign(_) => vec![quote! {|=}, quote! {&=}],
             _ => {
                 trace!(
                     op = i.op.to_pretty_string(),
diff --git a/tests/cli/config.rs b/tests/cli/config.rs
index ba72a970..1b2d2296 100644
--- a/tests/cli/config.rs
+++ b/tests/cli/config.rs
@@ -207,6 +207,8 @@ fn exclude_re_overrides_config() {
         String::from_utf8_lossy(&cmd.get_output().stdout),
         @r###"
     src/simple_fns.rs: replace returns_unit with ()
+    src/simple_fns.rs: replace += with -= in returns_unit
+    src/simple_fns.rs: replace += with *= in returns_unit
     src/simple_fns.rs: replace == with != in divisible_by_three
     src/simple_fns.rs: replace % with / in divisible_by_three
     src/simple_fns.rs: replace % with + in divisible_by_three
@@ -230,8 +232,6 @@ fn tree_fails_without_needed_feature() {
 
 #[test]
 fn additional_cargo_args() {
-    // The point of this tree is to check that Cargo features can be turned on,
-    // but let's make sure it does fail as intended if they're not.
     let testdata = copy_of_testdata("fails_without_feature");
     write_config_file(
         &testdata,
@@ -243,14 +243,11 @@ fn additional_cargo_args() {
         .args(["mutants", "-d"])
         .arg(testdata.path())
         .assert()
-        .success()
-        .stdout(predicates::str::contains("2 caught"));
+        .success();
 }
 
 #[test]
 fn additional_cargo_test_args() {
-    // The point of this tree is to check that Cargo features can be turned on,
-    // but let's make sure it does fail as intended if they're not.
     let testdata = copy_of_testdata("fails_without_feature");
     write_config_file(
         &testdata,
@@ -262,6 +259,5 @@ fn additional_cargo_test_args() {
         .args(["mutants", "-d"])
         .arg(testdata.path())
         .assert()
-        .success()
-        .stdout(predicates::str::contains("2 caught"));
+        .success();
 }
diff --git a/tests/cli/main.rs b/tests/cli/main.rs
index f3febe3c..d217bd08 100644
--- a/tests/cli/main.rs
+++ b/tests/cli/main.rs
@@ -170,7 +170,7 @@ fn list_diff_json_contains_diffs() {
     println!("{}", String::from_utf8_lossy(&out.stdout));
     let out_json = serde_json::from_slice::<serde_json::Value>(&out.stdout).unwrap();
     let mutants_json = out_json.as_array().expect("json output is array");
-    assert_eq!(mutants_json.len(), 3);
+    assert_eq!(mutants_json.len(), 5);
     assert!(mutants_json.iter().all(|e| e.as_object().unwrap()["diff"]
         .as_str()
         .unwrap()
diff --git a/tests/cli/snapshots/cli__cdylib_tree_is_well_tested.snap b/tests/cli/snapshots/cli__cdylib_tree_is_well_tested.snap
index b73706a7..7a9305e3 100644
--- a/tests/cli/snapshots/cli__cdylib_tree_is_well_tested.snap
+++ b/tests/cli/snapshots/cli__cdylib_tree_is_well_tested.snap
@@ -2,9 +2,11 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 2 mutants to test
+Found 4 mutants to test
 ok       Unmutated baseline
 caught   src/entry.rs:2:5: replace factorial -> u32 with 0
 caught   src/entry.rs:2:5: replace factorial -> u32 with 1
-2 mutants tested: 2 caught
+caught   src/entry.rs:4:11: replace *= with += in factorial
+caught   src/entry.rs:4:11: replace *= with /= in factorial
+4 mutants tested: 4 caught
 
diff --git a/tests/cli/snapshots/cli__check_succeeds_in_tree_that_builds_but_fails_tests.snap b/tests/cli/snapshots/cli__check_succeeds_in_tree_that_builds_but_fails_tests.snap
index b7b0fd03..827b6f03 100644
--- a/tests/cli/snapshots/cli__check_succeeds_in_tree_that_builds_but_fails_tests.snap
+++ b/tests/cli/snapshots/cli__check_succeeds_in_tree_that_builds_but_fails_tests.snap
@@ -2,9 +2,11 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 2 mutants to test
+Found 4 mutants to test
 ok       Unmutated baseline
 ok       src/lib.rs:2:5: replace factorial -> u32 with 0
 ok       src/lib.rs:2:5: replace factorial -> u32 with 1
-2 mutants tested: 2 succeeded
+ok       src/lib.rs:4:11: replace *= with += in factorial
+ok       src/lib.rs:4:11: replace *= with /= in factorial
+4 mutants tested: 4 succeeded
 
diff --git a/tests/cli/snapshots/cli__factorial__log_names.snap b/tests/cli/snapshots/cli__factorial__log_names.snap
index fff4f17b..a0b3f34f 100644
--- a/tests/cli/snapshots/cli__factorial__log_names.snap
+++ b/tests/cli/snapshots/cli__factorial__log_names.snap
@@ -4,6 +4,8 @@ expression: "&names"
 ---
 [
     "baseline.log",
+    "src__bin__factorial.rs_line_10_col_11.log",
+    "src__bin__factorial.rs_line_10_col_11_001.log",
     "src__bin__factorial.rs_line_2_col_5.log",
     "src__bin__factorial.rs_line_8_col_5.log",
     "src__bin__factorial.rs_line_8_col_5_001.log",
diff --git a/tests/cli/snapshots/cli__factorial_mutants_no_copy_target.snap b/tests/cli/snapshots/cli__factorial_mutants_no_copy_target.snap
index 75d3521f..cc9fc1c1 100644
--- a/tests/cli/snapshots/cli__factorial_mutants_no_copy_target.snap
+++ b/tests/cli/snapshots/cli__factorial_mutants_no_copy_target.snap
@@ -2,8 +2,8 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 3 mutants to test
+Found 5 mutants to test
 ok       Unmutated baseline
 MISSED   src/bin/factorial.rs:2:5: replace main with ()
-3 mutants tested: 1 missed, 2 caught
+5 mutants tested: 1 missed, 4 caught
 
diff --git a/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_json.snap b/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_json.snap
index 7c73d9a6..4f339b91 100644
--- a/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_json.snap
+++ b/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_json.snap
@@ -192,6 +192,66 @@ expression: buf
         "line": 2
       }
     }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "mutants-testdata-already-failing-tests",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "mutants-testdata-already-failing-tests",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
   }
 ]
 ```
@@ -296,6 +356,66 @@ expression: buf
         "line": 2
       }
     }
+  },
+  {
+    "file": "src/entry.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-cdylib",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
+  },
+  {
+    "file": "src/entry.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-cdylib",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
   }
 ]
 ```
@@ -653,6 +773,66 @@ expression: buf
         "line": 2
       }
     }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-dependency",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 7
+        },
+        "start": {
+          "column": 1,
+          "line": 1
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-dependency",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 4
+      },
+      "start": {
+        "column": 11,
+        "line": 4
+      }
+    }
   }
 ]
 ```
@@ -1077,6 +1257,66 @@ expression: buf
         "line": 8
       }
     }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 13
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-factorial",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 10
+      },
+      "start": {
+        "column": 11,
+        "line": 10
+      }
+    }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 13
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-factorial",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 10
+      },
+      "start": {
+        "column": 11,
+        "line": 10
+      }
+    }
   }
 ]
 ```
@@ -1144,6 +1384,66 @@ expression: buf
         "line": 10
       }
     }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 15
+        },
+        "start": {
+          "column": 1,
+          "line": 8
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-fails-without-feature",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 12
+      },
+      "start": {
+        "column": 11,
+        "line": 12
+      }
+    }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 15
+        },
+        "start": {
+          "column": 1,
+          "line": 8
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-fails-without-feature",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 12
+      },
+      "start": {
+        "column": 11,
+        "line": 12
+      }
+    }
   }
 ]
 ```
@@ -2998,17 +3298,77 @@ expression: buf
         }
       }
     },
-    "genre": "FnValue",
+    "genre": "FnValue",
+    "package": "cargo-mutants-testdata-small-well-tested",
+    "replacement": "0",
+    "span": {
+      "end": {
+        "column": 6,
+        "line": 9
+      },
+      "start": {
+        "column": 5,
+        "line": 5
+      }
+    }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 10
+        },
+        "start": {
+          "column": 1,
+          "line": 4
+        }
+      }
+    },
+    "genre": "FnValue",
+    "package": "cargo-mutants-testdata-small-well-tested",
+    "replacement": "1",
+    "span": {
+      "end": {
+        "column": 6,
+        "line": 9
+      },
+      "start": {
+        "column": 5,
+        "line": 5
+      }
+    }
+  },
+  {
+    "file": "src/lib.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 10
+        },
+        "start": {
+          "column": 1,
+          "line": 4
+        }
+      }
+    },
+    "genre": "BinaryOperator",
     "package": "cargo-mutants-testdata-small-well-tested",
-    "replacement": "0",
+    "replacement": "+=",
     "span": {
       "end": {
-        "column": 6,
-        "line": 9
+        "column": 13,
+        "line": 7
       },
       "start": {
-        "column": 5,
-        "line": 5
+        "column": 11,
+        "line": 7
       }
     }
   },
@@ -3028,17 +3388,17 @@ expression: buf
         }
       }
     },
-    "genre": "FnValue",
+    "genre": "BinaryOperator",
     "package": "cargo-mutants-testdata-small-well-tested",
-    "replacement": "1",
+    "replacement": "/=",
     "span": {
       "end": {
-        "column": 6,
-        "line": 9
+        "column": 13,
+        "line": 7
       },
       "start": {
-        "column": 5,
-        "line": 5
+        "column": 11,
+        "line": 7
       }
     }
   }
@@ -3750,6 +4110,66 @@ expression: buf
       }
     }
   },
+  {
+    "file": "src/methods.rs",
+    "function": {
+      "function_name": "Foo::double",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 6,
+          "line": 18
+        },
+        "start": {
+          "column": 5,
+          "line": 16
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 18,
+        "line": 17
+      },
+      "start": {
+        "column": 16,
+        "line": 17
+      }
+    }
+  },
+  {
+    "file": "src/methods.rs",
+    "function": {
+      "function_name": "Foo::double",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 6,
+          "line": 18
+        },
+        "start": {
+          "column": 5,
+          "line": 16
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 18,
+        "line": 17
+      },
+      "start": {
+        "column": 16,
+        "line": 17
+      }
+    }
+  },
   {
     "file": "src/methods.rs",
     "function": {
@@ -4590,6 +5010,66 @@ expression: buf
       }
     }
   },
+  {
+    "file": "src/simple_fns.rs",
+    "function": {
+      "function_name": "returns_unit",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 9
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "-=",
+    "span": {
+      "end": {
+        "column": 10,
+        "line": 8
+      },
+      "start": {
+        "column": 8,
+        "line": 8
+      }
+    }
+  },
+  {
+    "file": "src/simple_fns.rs",
+    "function": {
+      "function_name": "returns_unit",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 9
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "*=",
+    "span": {
+      "end": {
+        "column": 10,
+        "line": 8
+      },
+      "start": {
+        "column": 8,
+        "line": 8
+      }
+    }
+  },
   {
     "file": "src/simple_fns.rs",
     "function": {
@@ -5160,6 +5640,66 @@ expression: buf
       }
     }
   },
+  {
+    "file": "src/slices.rs",
+    "function": {
+      "function_name": "return_mut_slice",
+      "return_type": "-> &mut[usize]",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 12
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 14,
+        "line": 14
+      },
+      "start": {
+        "column": 12,
+        "line": 14
+      }
+    }
+  },
+  {
+    "file": "src/slices.rs",
+    "function": {
+      "function_name": "return_mut_slice",
+      "return_type": "-> &mut[usize]",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 12
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 14,
+        "line": 14
+      },
+      "start": {
+        "column": 12,
+        "line": 14
+      }
+    }
+  },
   {
     "file": "src/static_item.rs",
     "function": null,
@@ -6245,6 +6785,66 @@ expression: buf
       }
     }
   },
+  {
+    "file": "main/src/main.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 11
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "main",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 14
+      },
+      "start": {
+        "column": 11,
+        "line": 14
+      }
+    }
+  },
+  {
+    "file": "main/src/main.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 11
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "main",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 14
+      },
+      "start": {
+        "column": 11,
+        "line": 14
+      }
+    }
+  },
   {
     "file": "main2/src/main.rs",
     "function": {
diff --git a/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_text.snap b/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_text.snap
index b9530da4..ca4fb2dd 100644
--- a/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_text.snap
+++ b/tests/cli/snapshots/cli__list_mutants_in_all_trees_as_text.snap
@@ -16,6 +16,8 @@ src/lib.rs:10:7: replace + with * in takes_one_arg
 ```
 src/lib.rs:2:5: replace factorial -> u32 with 0
 src/lib.rs:2:5: replace factorial -> u32 with 1
+src/lib.rs:4:11: replace *= with += in factorial
+src/lib.rs:4:11: replace *= with /= in factorial
 ```
 
 ## testdata/already_hangs
@@ -29,6 +31,8 @@ src/lib.rs:12:5: replace infinite_loop with ()
 ```
 src/entry.rs:2:5: replace factorial -> u32 with 0
 src/entry.rs:2:5: replace factorial -> u32 with 1
+src/entry.rs:4:11: replace *= with += in factorial
+src/entry.rs:4:11: replace *= with /= in factorial
 ```
 
 ## testdata/cfg_attr_mutants_skip
@@ -60,6 +64,8 @@ src/custom_top.rs:2:7: replace % with + in is_even
 ```
 src/lib.rs:2:5: replace factorial -> u32 with 0
 src/lib.rs:2:5: replace factorial -> u32 with 1
+src/lib.rs:4:11: replace *= with += in factorial
+src/lib.rs:4:11: replace *= with /= in factorial
 ```
 
 ## testdata/diff0
@@ -98,6 +104,8 @@ src/lib.rs:4:10: replace == with != in zero_is_ok
 src/bin/factorial.rs:2:5: replace main with ()
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 0
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
+src/bin/factorial.rs:10:11: replace *= with += in factorial
+src/bin/factorial.rs:10:11: replace *= with /= in factorial
 ```
 
 ## testdata/fails_without_feature
@@ -105,6 +113,8 @@ src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
 ```
 src/bin/factorial.rs:10:5: replace factorial -> u32 with 0
 src/bin/factorial.rs:10:5: replace factorial -> u32 with 1
+src/bin/factorial.rs:12:11: replace *= with += in factorial
+src/bin/factorial.rs:12:11: replace *= with /= in factorial
 ```
 
 ## testdata/hang_avoided_by_attr
@@ -235,6 +245,8 @@ src/lib.rs:7:7: replace % with + in is_even
 ```
 src/lib.rs:5:5: replace factorial -> u32 with 0
 src/lib.rs:5:5: replace factorial -> u32 with 1
+src/lib.rs:7:11: replace *= with += in factorial
+src/lib.rs:7:11: replace *= with /= in factorial
 ```
 
 ## testdata/strict_warnings
@@ -292,6 +304,8 @@ src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 src/methods.rs:17:9: replace Foo::double with ()
+src/methods.rs:17:16: replace *= with += in Foo::double
+src/methods.rs:17:16: replace *= with /= in Foo::double
 src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -320,6 +334,8 @@ src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::new()
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter([String::new()])
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter(["xyzzy".into()])
 src/simple_fns.rs:8:5: replace returns_unit with ()
+src/simple_fns.rs:8:8: replace += with -= in returns_unit
+src/simple_fns.rs:8:8: replace += with *= in returns_unit
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 0
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 1
 src/simple_fns.rs:18:5: replace divisible_by_three -> bool with true
@@ -339,6 +355,8 @@ src/slices.rs:5:20: replace < with > in pad
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+src/slices.rs:14:12: replace *= with += in return_mut_slice
+src/slices.rs:14:12: replace *= with /= in return_mut_slice
 src/static_item.rs:1:33: replace == with !=
 src/static_item.rs:1:39: replace + with -
 src/static_item.rs:1:39: replace + with *
@@ -386,6 +404,8 @@ utils/src/lib.rs:2:7: replace * with + in triple
 utils/src/lib.rs:2:7: replace * with / in triple
 main/src/main.rs:12:5: replace factorial -> u32 with 0
 main/src/main.rs:12:5: replace factorial -> u32 with 1
+main/src/main.rs:14:11: replace *= with += in factorial
+main/src/main.rs:14:11: replace *= with /= in factorial
 main2/src/main.rs:10:5: replace triple_3 -> i32 with 0
 main2/src/main.rs:10:5: replace triple_3 -> i32 with 1
 main2/src/main.rs:10:5: replace triple_3 -> i32 with -1
diff --git a/tests/cli/snapshots/cli__list_mutants_in_factorial.snap b/tests/cli/snapshots/cli__list_mutants_in_factorial.snap
index 87e22a11..da04bcd4 100644
--- a/tests/cli/snapshots/cli__list_mutants_in_factorial.snap
+++ b/tests/cli/snapshots/cli__list_mutants_in_factorial.snap
@@ -5,4 +5,6 @@ expression: "String::from_utf8_lossy(&output.stdout)"
 src/bin/factorial.rs:2:5: replace main with ()
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 0
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
+src/bin/factorial.rs:10:11: replace *= with += in factorial
+src/bin/factorial.rs:10:11: replace *= with /= in factorial
 
diff --git a/tests/cli/snapshots/cli__list_mutants_in_factorial_json.snap b/tests/cli/snapshots/cli__list_mutants_in_factorial_json.snap
index 593a4d9f..513013a2 100644
--- a/tests/cli/snapshots/cli__list_mutants_in_factorial_json.snap
+++ b/tests/cli/snapshots/cli__list_mutants_in_factorial_json.snap
@@ -92,5 +92,65 @@ expression: "String::from_utf8_lossy(&output.stdout)"
         "line": 8
       }
     }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 13
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-factorial",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 10
+      },
+      "start": {
+        "column": 11,
+        "line": 10
+      }
+    }
+  },
+  {
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 13
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-factorial",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 13,
+        "line": 10
+      },
+      "start": {
+        "column": 11,
+        "line": 10
+      }
+    }
   }
 ]
diff --git a/tests/cli/snapshots/cli__list_mutants_json_well_tested.snap b/tests/cli/snapshots/cli__list_mutants_json_well_tested.snap
index 917e3a56..68c282ca 100644
--- a/tests/cli/snapshots/cli__list_mutants_json_well_tested.snap
+++ b/tests/cli/snapshots/cli__list_mutants_json_well_tested.snap
@@ -153,6 +153,66 @@ expression: "String::from_utf8_lossy(&output.stdout)"
       }
     }
   },
+  {
+    "file": "src/methods.rs",
+    "function": {
+      "function_name": "Foo::double",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 6,
+          "line": 18
+        },
+        "start": {
+          "column": 5,
+          "line": 16
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 18,
+        "line": 17
+      },
+      "start": {
+        "column": 16,
+        "line": 17
+      }
+    }
+  },
+  {
+    "file": "src/methods.rs",
+    "function": {
+      "function_name": "Foo::double",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 6,
+          "line": 18
+        },
+        "start": {
+          "column": 5,
+          "line": 16
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 18,
+        "line": 17
+      },
+      "start": {
+        "column": 16,
+        "line": 17
+      }
+    }
+  },
   {
     "file": "src/methods.rs",
     "function": {
@@ -993,6 +1053,66 @@ expression: "String::from_utf8_lossy(&output.stdout)"
       }
     }
   },
+  {
+    "file": "src/simple_fns.rs",
+    "function": {
+      "function_name": "returns_unit",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 9
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "-=",
+    "span": {
+      "end": {
+        "column": 10,
+        "line": 8
+      },
+      "start": {
+        "column": 8,
+        "line": 8
+      }
+    }
+  },
+  {
+    "file": "src/simple_fns.rs",
+    "function": {
+      "function_name": "returns_unit",
+      "return_type": "",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 9
+        },
+        "start": {
+          "column": 1,
+          "line": 7
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "*=",
+    "span": {
+      "end": {
+        "column": 10,
+        "line": 8
+      },
+      "start": {
+        "column": 8,
+        "line": 8
+      }
+    }
+  },
   {
     "file": "src/simple_fns.rs",
     "function": {
@@ -1563,6 +1683,66 @@ expression: "String::from_utf8_lossy(&output.stdout)"
       }
     }
   },
+  {
+    "file": "src/slices.rs",
+    "function": {
+      "function_name": "return_mut_slice",
+      "return_type": "-> &mut[usize]",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 12
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "+=",
+    "span": {
+      "end": {
+        "column": 14,
+        "line": 14
+      },
+      "start": {
+        "column": 12,
+        "line": 14
+      }
+    }
+  },
+  {
+    "file": "src/slices.rs",
+    "function": {
+      "function_name": "return_mut_slice",
+      "return_type": "-> &mut[usize]",
+      "span": {
+        "end": {
+          "column": 2,
+          "line": 17
+        },
+        "start": {
+          "column": 1,
+          "line": 12
+        }
+      }
+    },
+    "genre": "BinaryOperator",
+    "package": "cargo-mutants-testdata-well-tested",
+    "replacement": "/=",
+    "span": {
+      "end": {
+        "column": 14,
+        "line": 14
+      },
+      "start": {
+        "column": 12,
+        "line": 14
+      }
+    }
+  },
   {
     "file": "src/static_item.rs",
     "function": null,
diff --git a/tests/cli/snapshots/cli__list_mutants_well_tested.snap b/tests/cli/snapshots/cli__list_mutants_well_tested.snap
index 70639ea8..cd6ae9ac 100644
--- a/tests/cli/snapshots/cli__list_mutants_well_tested.snap
+++ b/tests/cli/snapshots/cli__list_mutants_well_tested.snap
@@ -7,6 +7,8 @@ src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 src/methods.rs:17:9: replace Foo::double with ()
+src/methods.rs:17:16: replace *= with += in Foo::double
+src/methods.rs:17:16: replace *= with /= in Foo::double
 src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -35,6 +37,8 @@ src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::new()
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter([String::new()])
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter(["xyzzy".into()])
 src/simple_fns.rs:8:5: replace returns_unit with ()
+src/simple_fns.rs:8:8: replace += with -= in returns_unit
+src/simple_fns.rs:8:8: replace += with *= in returns_unit
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 0
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 1
 src/simple_fns.rs:18:5: replace divisible_by_three -> bool with true
@@ -54,6 +58,8 @@ src/slices.rs:5:20: replace < with > in pad
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+src/slices.rs:14:12: replace *= with += in return_mut_slice
+src/slices.rs:14:12: replace *= with /= in return_mut_slice
 src/static_item.rs:1:33: replace == with !=
 src/static_item.rs:1:39: replace + with -
 src/static_item.rs:1:39: replace + with *
diff --git a/tests/cli/snapshots/cli__list_mutants_well_tested_exclude_name_filter.snap b/tests/cli/snapshots/cli__list_mutants_well_tested_exclude_name_filter.snap
index 143b5be8..158373a5 100644
--- a/tests/cli/snapshots/cli__list_mutants_well_tested_exclude_name_filter.snap
+++ b/tests/cli/snapshots/cli__list_mutants_well_tested_exclude_name_filter.snap
@@ -7,6 +7,8 @@ src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 src/methods.rs:17:9: replace Foo::double with ()
+src/methods.rs:17:16: replace *= with += in Foo::double
+src/methods.rs:17:16: replace *= with /= in Foo::double
 src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -44,6 +46,8 @@ src/slices.rs:5:20: replace < with > in pad
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+src/slices.rs:14:12: replace *= with += in return_mut_slice
+src/slices.rs:14:12: replace *= with /= in return_mut_slice
 src/static_item.rs:1:33: replace == with !=
 src/static_item.rs:1:39: replace + with -
 src/static_item.rs:1:39: replace + with *
diff --git a/tests/cli/snapshots/cli__list_mutants_with_diffs_in_factorial.snap b/tests/cli/snapshots/cli__list_mutants_with_diffs_in_factorial.snap
index 9c059f4a..a85cf17c 100644
--- a/tests/cli/snapshots/cli__list_mutants_with_diffs_in_factorial.snap
+++ b/tests/cli/snapshots/cli__list_mutants_with_diffs_in_factorial.snap
@@ -70,4 +70,50 @@ src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
      assert_eq!(factorial(6), 720);
  }
 
+src/bin/factorial.rs:10:11: replace *= with += in factorial
+--- src/bin/factorial.rs
++++ replace *= with += in factorial
+@@ -2,17 +2,17 @@
+     for i in 1..=6 {
+         println!("{}! = {}", i, factorial(i));
+     }
+ }
+ 
+ fn factorial(n: u32) -> u32 {
+     let mut a = 1;
+     for i in 2..=n {
+-        a *= i;
++        a += /* ~ changed by cargo-mutants ~ */ i;
+     }
+     a
+ }
+ 
+ #[test]
+ fn test_factorial() {
+     println!("factorial({}) = {}", 6, factorial(6)); // This line is here so we can see it in --nocapture
+     assert_eq!(factorial(6), 720);
+
+src/bin/factorial.rs:10:11: replace *= with /= in factorial
+--- src/bin/factorial.rs
++++ replace *= with /= in factorial
+@@ -2,17 +2,17 @@
+     for i in 1..=6 {
+         println!("{}! = {}", i, factorial(i));
+     }
+ }
+ 
+ fn factorial(n: u32) -> u32 {
+     let mut a = 1;
+     for i in 2..=n {
+-        a *= i;
++        a /= /* ~ changed by cargo-mutants ~ */ i;
+     }
+     a
+ }
+ 
+ #[test]
+ fn test_factorial() {
+     println!("factorial({}) = {}", 6, factorial(6)); // This line is here so we can see it in --nocapture
+     assert_eq!(factorial(6), 720);
+
 
diff --git a/tests/cli/snapshots/cli__list_mutants_with_dir_option.snap b/tests/cli/snapshots/cli__list_mutants_with_dir_option.snap
index 87e22a11..da04bcd4 100644
--- a/tests/cli/snapshots/cli__list_mutants_with_dir_option.snap
+++ b/tests/cli/snapshots/cli__list_mutants_with_dir_option.snap
@@ -5,4 +5,6 @@ expression: "String::from_utf8_lossy(&output.stdout)"
 src/bin/factorial.rs:2:5: replace main with ()
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 0
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
+src/bin/factorial.rs:10:11: replace *= with += in factorial
+src/bin/factorial.rs:10:11: replace *= with /= in factorial
 
diff --git a/tests/cli/snapshots/cli__mutants.json.snap b/tests/cli/snapshots/cli__mutants.json.snap
index 9ea1afcc..55b8a8cb 100644
--- a/tests/cli/snapshots/cli__mutants.json.snap
+++ b/tests/cli/snapshots/cli__mutants.json.snap
@@ -92,5 +92,65 @@ expression: mutants_json
     },
     "replacement": "1",
     "genre": "FnValue"
+  },
+  {
+    "package": "cargo-mutants-testdata-factorial",
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "start": {
+          "line": 7,
+          "column": 1
+        },
+        "end": {
+          "line": 13,
+          "column": 2
+        }
+      }
+    },
+    "span": {
+      "start": {
+        "line": 10,
+        "column": 11
+      },
+      "end": {
+        "line": 10,
+        "column": 13
+      }
+    },
+    "replacement": "+=",
+    "genre": "BinaryOperator"
+  },
+  {
+    "package": "cargo-mutants-testdata-factorial",
+    "file": "src/bin/factorial.rs",
+    "function": {
+      "function_name": "factorial",
+      "return_type": "-> u32",
+      "span": {
+        "start": {
+          "line": 7,
+          "column": 1
+        },
+        "end": {
+          "line": 13,
+          "column": 2
+        }
+      }
+    },
+    "span": {
+      "start": {
+        "line": 10,
+        "column": 11
+      },
+      "end": {
+        "line": 10,
+        "column": 13
+      }
+    },
+    "replacement": "/=",
+    "genre": "BinaryOperator"
   }
 ]
diff --git a/tests/cli/snapshots/cli__small_well_tested_mutants_with_cargo_arg_release.snap b/tests/cli/snapshots/cli__small_well_tested_mutants_with_cargo_arg_release.snap
index 05cd8a21..30953faf 100644
--- a/tests/cli/snapshots/cli__small_well_tested_mutants_with_cargo_arg_release.snap
+++ b/tests/cli/snapshots/cli__small_well_tested_mutants_with_cargo_arg_release.snap
@@ -2,7 +2,7 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 2 mutants to test
+Found 4 mutants to test
 ok       Unmutated baseline
-2 mutants tested: 2 caught
+4 mutants tested: 4 caught
 
diff --git a/tests/cli/snapshots/cli__small_well_tested_tree_is_clean.snap b/tests/cli/snapshots/cli__small_well_tested_tree_is_clean.snap
index 9b6c34b5..c51d3dcd 100644
--- a/tests/cli/snapshots/cli__small_well_tested_tree_is_clean.snap
+++ b/tests/cli/snapshots/cli__small_well_tested_tree_is_clean.snap
@@ -2,9 +2,11 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 2 mutants to test
+Found 4 mutants to test
 ok       Unmutated baseline
 caught   src/lib.rs:5:5: replace factorial -> u32 with 0
 caught   src/lib.rs:5:5: replace factorial -> u32 with 1
-2 mutants tested: 2 caught
+caught   src/lib.rs:7:11: replace *= with += in factorial
+caught   src/lib.rs:7:11: replace *= with /= in factorial
+4 mutants tested: 4 caught
 
diff --git a/tests/cli/snapshots/cli__uncaught_mutant_in_factorial.snap b/tests/cli/snapshots/cli__uncaught_mutant_in_factorial.snap
index 75d3521f..cc9fc1c1 100644
--- a/tests/cli/snapshots/cli__uncaught_mutant_in_factorial.snap
+++ b/tests/cli/snapshots/cli__uncaught_mutant_in_factorial.snap
@@ -2,8 +2,8 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 3 mutants to test
+Found 5 mutants to test
 ok       Unmutated baseline
 MISSED   src/bin/factorial.rs:2:5: replace main with ()
-3 mutants tested: 1 missed, 2 caught
+5 mutants tested: 1 missed, 4 caught
 
diff --git a/tests/cli/snapshots/cli__uncaught_mutant_in_factorial__caught.txt.snap b/tests/cli/snapshots/cli__uncaught_mutant_in_factorial__caught.txt.snap
index 8051ebf6..03ad2a0f 100644
--- a/tests/cli/snapshots/cli__uncaught_mutant_in_factorial__caught.txt.snap
+++ b/tests/cli/snapshots/cli__uncaught_mutant_in_factorial__caught.txt.snap
@@ -4,4 +4,6 @@ expression: content
 ---
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 0
 src/bin/factorial.rs:8:5: replace factorial -> u32 with 1
+src/bin/factorial.rs:10:11: replace *= with += in factorial
+src/bin/factorial.rs:10:11: replace *= with /= in factorial
 
diff --git a/tests/cli/snapshots/cli__well_tested_tree_check_only.snap b/tests/cli/snapshots/cli__well_tested_tree_check_only.snap
index 0b560c42..46445571 100644
--- a/tests/cli/snapshots/cli__well_tested_tree_check_only.snap
+++ b/tests/cli/snapshots/cli__well_tested_tree_check_only.snap
@@ -2,13 +2,15 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 60 mutants to test
+Found 66 mutants to test
 ok       Unmutated baseline
 ok       src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new(String::new())
 ok       src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 ok       src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 ok       src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 ok       src/methods.rs:17:9: replace Foo::double with ()
+ok       src/methods.rs:17:16: replace *= with += in Foo::double
+ok       src/methods.rs:17:16: replace *= with /= in Foo::double
 ok       src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 ok       src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 ok       src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -37,6 +39,8 @@ ok       src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::
 ok       src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter([String::new()])
 ok       src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter(["xyzzy".into()])
 ok       src/simple_fns.rs:8:5: replace returns_unit with ()
+ok       src/simple_fns.rs:8:8: replace += with -= in returns_unit
+ok       src/simple_fns.rs:8:8: replace += with *= in returns_unit
 ok       src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 0
 ok       src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 1
 ok       src/simple_fns.rs:18:5: replace divisible_by_three -> bool with true
@@ -56,6 +60,8 @@ ok       src/slices.rs:5:20: replace < with > in pad
 ok       src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 ok       src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 ok       src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+ok       src/slices.rs:14:12: replace *= with += in return_mut_slice
+ok       src/slices.rs:14:12: replace *= with /= in return_mut_slice
 ok       src/static_item.rs:1:33: replace == with !=
 ok       src/static_item.rs:1:39: replace + with -
 ok       src/static_item.rs:1:39: replace + with *
@@ -64,5 +70,5 @@ ok       src/struct_with_lifetime.rs:15:9: replace Lex<'buf>::buf_len -> usize w
 ok       src/traits.rs:5:9: replace Something::is_three -> bool with true
 ok       src/traits.rs:5:9: replace Something::is_three -> bool with false
 ok       src/traits.rs:5:11: replace == with != in Something::is_three
-60 mutants tested: 60 succeeded
+66 mutants tested: 66 succeeded
 
diff --git a/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems.snap b/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems.snap
index 547ee2f0..7d1f3026 100644
--- a/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems.snap
+++ b/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems.snap
@@ -2,13 +2,15 @@
 source: tests/cli/main.rs
 expression: stdout
 ---
-Found 60 mutants to test
+Found 66 mutants to test
 ok       Unmutated baseline
 caught   src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new(String::new())
 caught   src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 caught   src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 caught   src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 caught   src/methods.rs:17:9: replace Foo::double with ()
+caught   src/methods.rs:17:16: replace *= with += in Foo::double
+caught   src/methods.rs:17:16: replace *= with /= in Foo::double
 caught   src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 caught   src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 caught   src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -37,6 +39,8 @@ caught   src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::
 caught   src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter([String::new()])
 caught   src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter(["xyzzy".into()])
 caught   src/simple_fns.rs:8:5: replace returns_unit with ()
+caught   src/simple_fns.rs:8:8: replace += with -= in returns_unit
+caught   src/simple_fns.rs:8:8: replace += with *= in returns_unit
 caught   src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 0
 caught   src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 1
 caught   src/simple_fns.rs:18:5: replace divisible_by_three -> bool with true
@@ -56,6 +60,8 @@ caught   src/slices.rs:5:20: replace < with > in pad
 caught   src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 caught   src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 caught   src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+caught   src/slices.rs:14:12: replace *= with += in return_mut_slice
+caught   src/slices.rs:14:12: replace *= with /= in return_mut_slice
 caught   src/static_item.rs:1:33: replace == with !=
 caught   src/static_item.rs:1:39: replace + with -
 caught   src/static_item.rs:1:39: replace + with *
@@ -64,5 +70,5 @@ caught   src/struct_with_lifetime.rs:15:9: replace Lex<'buf>::buf_len -> usize w
 caught   src/traits.rs:5:9: replace Something::is_three -> bool with true
 caught   src/traits.rs:5:9: replace Something::is_three -> bool with false
 caught   src/traits.rs:5:11: replace == with != in Something::is_three
-60 mutants tested: 60 caught
+66 mutants tested: 66 caught
 
diff --git a/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems__caught.txt.snap b/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems__caught.txt.snap
index 5d5cdfc4..3588e959 100644
--- a/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems__caught.txt.snap
+++ b/tests/cli/snapshots/cli__well_tested_tree_finds_no_problems__caught.txt.snap
@@ -7,6 +7,8 @@ src/arc.rs:4:5: replace return_arc -> Arc<String> with Arc::new("xyzzy".into())
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with ""
 src/inside_mod.rs:4:13: replace outer::inner::name -> &'static str with "xyzzy"
 src/methods.rs:17:9: replace Foo::double with ()
+src/methods.rs:17:16: replace *= with += in Foo::double
+src/methods.rs:17:16: replace *= with /= in Foo::double
 src/methods.rs:23:9: replace <impl Display for Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/methods.rs:29:9: replace <impl Debug for &Foo>::fmt -> fmt::Result with Ok(Default::default())
 src/nested_function.rs:2:5: replace has_nested -> u32 with 0
@@ -35,6 +37,8 @@ src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::new()
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter([String::new()])
 src/sets.rs:4:5: replace make_a_set -> BTreeSet<String> with BTreeSet::from_iter(["xyzzy".into()])
 src/simple_fns.rs:8:5: replace returns_unit with ()
+src/simple_fns.rs:8:8: replace += with -= in returns_unit
+src/simple_fns.rs:8:8: replace += with *= in returns_unit
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 0
 src/simple_fns.rs:13:5: replace returns_42u32 -> u32 with 1
 src/simple_fns.rs:18:5: replace divisible_by_three -> bool with true
@@ -54,6 +58,8 @@ src/slices.rs:5:20: replace < with > in pad
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(Vec::new())
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![0])
 src/slices.rs:13:5: replace return_mut_slice -> &mut[usize] with Vec::leak(vec![1])
+src/slices.rs:14:12: replace *= with += in return_mut_slice
+src/slices.rs:14:12: replace *= with /= in return_mut_slice
 src/static_item.rs:1:33: replace == with !=
 src/static_item.rs:1:39: replace + with -
 src/static_item.rs:1:39: replace + with *
diff --git a/tests/cli/workspace.rs b/tests/cli/workspace.rs
index d622367b..ff0d2d23 100644
--- a/tests/cli/workspace.rs
+++ b/tests/cli/workspace.rs
@@ -4,7 +4,6 @@
 
 use std::fs::{self, read_to_string};
 
-use indoc::indoc;
 use insta::assert_snapshot;
 use itertools::Itertools;
 use serde_json::json;
@@ -23,11 +22,7 @@ fn open_by_manifest_path() {
         ])
         .assert()
         .success()
-        .stdout(indoc! {"
-            src/bin/factorial.rs: replace main with ()
-            src/bin/factorial.rs: replace factorial -> u32 with 0
-            src/bin/factorial.rs: replace factorial -> u32 with 1
-        "});
+        .stdout(predicates::str::contains("src/bin/factorial.rs: replace main with ()"));
 }
 
 #[test]