From f12018eba11f8d4b74cf67dbc416c429c870a5f4 Mon Sep 17 00:00:00 2001
From: Congcong Cai <congcongcai0907@163.com>
Date: Tue, 14 May 2024 09:48:57 +0800
Subject: [PATCH] [clang-tidy] support expect no diagnosis test (#91293)
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When someone wants to declare a test case without any diagnosis.
check-clang-tidy will failed with error message

```
CHECK-FIXES, CHECK-MESSAGES or CHECK-NOTES not found in the input
```

This PR want to check there are no diagnosis from clang-tidy when
CHECK-FIXES, CHECK-MESSAGES or CHECK-NOTES are not found.

It also changes the extension of a test case. `hxx` is not a valid test
case extension and won't be tested.

---------

Co-authored-by: Danny Mösch <danny.moesch@icloud.com>
---
 .../test/clang-tidy/check_clang_tidy.py       | 28 +++++++++++++++----
 .../checkers/misc/unused-using-decls.hpp      |  6 ++++
 .../checkers/misc/unused-using-decls.hxx      |  6 ----
 3 files changed, 28 insertions(+), 12 deletions(-)
 create mode 100644 clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hpp
 delete mode 100644 clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hxx

diff --git a/clang-tools-extra/test/clang-tidy/check_clang_tidy.py b/clang-tools-extra/test/clang-tidy/check_clang_tidy.py
index 6d4b466afa691a..e92179ac82c6a0 100755
--- a/clang-tools-extra/test/clang-tidy/check_clang_tidy.py
+++ b/clang-tools-extra/test/clang-tidy/check_clang_tidy.py
@@ -99,6 +99,7 @@ def __init__(self, args, extra_args):
         self.has_check_fixes = False
         self.has_check_messages = False
         self.has_check_notes = False
+        self.expect_no_diagnosis = False
         self.export_fixes = args.export_fixes
         self.fixes = MessagePrefix("CHECK-FIXES")
         self.messages = MessagePrefix("CHECK-MESSAGES")
@@ -172,12 +173,21 @@ def get_prefixes(self):
                 )
 
             if not has_check_fix and not has_check_message and not has_check_note:
-                sys.exit(
-                    "%s, %s or %s not found in the input"
-                    % (self.fixes.prefix, self.messages.prefix, self.notes.prefix)
-                )
+                self.expect_no_diagnosis = True
 
-        assert self.has_check_fixes or self.has_check_messages or self.has_check_notes
+        expect_diagnosis = (
+            self.has_check_fixes or self.has_check_messages or self.has_check_notes
+        )
+        if self.expect_no_diagnosis and expect_diagnosis:
+            sys.exit(
+                "%s, %s or %s not found in the input"
+                % (
+                    self.fixes.prefix,
+                    self.messages.prefix,
+                    self.notes.prefix,
+                )
+            )
+        assert expect_diagnosis or self.expect_no_diagnosis
 
     def prepare_test_inputs(self):
         # Remove the contents of the CHECK lines to avoid CHECKs matching on
@@ -226,6 +236,10 @@ def run_clang_tidy(self):
         print("------------------------------------------------------------------")
         return clang_tidy_output
 
+    def check_no_diagnosis(self, clang_tidy_output):
+        if clang_tidy_output != "":
+            sys.exit("No diagnostics were expected, but found the ones above")
+
     def check_fixes(self):
         if self.has_check_fixes:
             try_run(
@@ -277,7 +291,9 @@ def run(self):
             self.get_prefixes()
         self.prepare_test_inputs()
         clang_tidy_output = self.run_clang_tidy()
-        if self.export_fixes is None:
+        if self.expect_no_diagnosis:
+            self.check_no_diagnosis(clang_tidy_output)
+        elif self.export_fixes is None:
             self.check_fixes()
             self.check_messages(clang_tidy_output)
             self.check_notes(clang_tidy_output)
diff --git a/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hpp b/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hpp
new file mode 100644
index 00000000000000..4918aae16cb94a
--- /dev/null
+++ b/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hpp
@@ -0,0 +1,6 @@
+// RUN: %check_clang_tidy %s misc-unused-using-decls %t
+
+// Verify that we don't generate the warnings on header files.
+namespace foo { class Foo {}; }
+
+using foo::Foo;
diff --git a/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hxx b/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hxx
deleted file mode 100644
index f15e4fae80c0bc..00000000000000
--- a/clang-tools-extra/test/clang-tidy/checkers/misc/unused-using-decls.hxx
+++ /dev/null
@@ -1,6 +0,0 @@
-// RUN: %check_clang_tidy %s misc-unused-using-decls %t -- --fix-notes -- -fno-delayed-template-parsing -isystem %S/Inputs
-
-// Verify that we don't generate the warnings on header files.
-namespace foo { class Foo {}; }
-
-using foo::Foo;