Add inferred empty else to switch states

peartreegames · Jun 12, 2024 · 0edb3ea · 0edb3ea
1 parent 6bcce25
commit 0edb3ea
Show file tree

Hide file tree

Showing 9 changed files with 49 additions and 13 deletions.
diff --git a/.gitignore b/.gitignore
@@ -1,5 +1,5 @@
 .idea
 .DS_Store
-zig-cache
+.zig-cache
 zig-out
-*.topib
+*.topib
diff --git a/README.md b/README.md
@@ -69,7 +69,7 @@ and [LoLa](https://github.com/MasterQ32/LoLa/tree/master) both of which are cred
 
 ## Contributing
 
-Download and install [Zig](https://ziglang.org). Currently Topiary uses version `0.12.0`
+Download and install [Zig](https://ziglang.org). Currently Topiary uses version `0.13.0`
 
 ```
 git clone https://github.com/peartreegames/topiary

diff --git a/build.zig b/build.zig
@@ -5,12 +5,12 @@ pub fn build(b: *std.Build) void {
     const optimize = b.standardOptimizeOption(.{});
 
     _ = b.addModule("topi", .{
-        .root_source_file = .{ .path = "src/topi.zig" },
+        .root_source_file = b.path("src/topi.zig"),
     });
 
     const topidll = b.addSharedLibrary(.{
         .name = "topi",
-        .root_source_file = .{ .path = "src/export.zig" },
+        .root_source_file = b.path("src/export.zig"),
         .target = target,
         .optimize = optimize,
     });
@@ -19,7 +19,7 @@ pub fn build(b: *std.Build) void {
 
     const exe = b.addExecutable(.{
         .name = "topi",
-        .root_source_file = .{ .path = "src/cli.zig" },
+        .root_source_file = b.path("src/cli.zig"),
         .target = target,
         .optimize = optimize,
     });
@@ -36,7 +36,7 @@ pub fn build(b: *std.Build) void {
     run_step.dependOn(&run_cmd.step);
 
     const tests = b.addTest(.{
-        .root_source_file = .{ .path = "src/vm.zig" },
+        .root_source_file = b.path("src/vm.zig"),
         .target = target,
         .optimize = optimize,
     });

diff --git a/build.zig.zon b/build.zig.zon
@@ -1,6 +1,6 @@
 .{
     .name = "topiary",
-    .version = "0.13.1",
+    .version = "0.13.2",
     .paths = .{""},
     .dependencies = .{},
 }
diff --git a/src/cli.zig b/src/cli.zig
@@ -75,7 +75,7 @@ pub fn main() !void {
     }
 
     const is_run = std.mem.eql(u8, cmd, "run");
-    const is_test = std.mem.eql(u8, cmd, "auto");
+    const is_test = std.mem.eql(u8, cmd, "test");
     const is_compile = std.mem.eql(u8, cmd, "compile");
     const is_loc = std.mem.eql(u8, cmd, "loc");
     if (!is_run and !is_test and !is_compile and !is_loc) return usage("Unknown command");

diff --git a/src/compiler.zig b/src/compiler.zig
@@ -345,20 +345,31 @@ pub const Compiler = struct {
                 const start = self.instructionPos();
                 try self.compileExpression(&s.capture);
                 var prong_jumps = try self.allocator.alloc(usize, s.prongs.len);
+                var inferred_else_jump: ?usize = null;
                 defer self.allocator.free(prong_jumps);
                 // compile expressions and jumps
+                var has_else = false;
                 for (s.prongs, 0..) |prong_stmt, i| {
                     const prong = prong_stmt.type.switch_prong;
                     if (prong.values) |p| {
                         for (p) |value| {
                             try self.compileExpression(&value);
                         }
+                    } else {
+                        has_else = true;
                     }
                     try self.writeOp(.prong, prong_stmt.token);
                     const prong_jump = try self.writeInt(OpCode.Size(.jump), PRONG_HOLDER, prong_stmt.token);
                     _ = try self.writeInt(u8, @as(u8, @intCast(if (prong.values) |p| p.len else 0)), prong_stmt.token);
                     prong_jumps[i] = prong_jump;
                 }
+                // add an empty else if none found
+                if (!has_else) {
+                    try self.writeOp(.prong, token);
+                    const prong_jump = try self.writeInt(OpCode.Size(.jump), PRONG_HOLDER, token);
+                    _ = try self.writeInt(u8, 0, token);
+                    inferred_else_jump = prong_jump;
+                }
 
                 // replace jumps and compile body
                 for (s.prongs, 0..) |prong_stmt, i| {
@@ -370,6 +381,16 @@ pub const Compiler = struct {
                     _ = try self.writeInt(OpCode.Size(.jump), SWITCH_END_HOLDER, prong_stmt.token);
                     try self.exitScope();
                 }
+
+                if (inferred_else_jump) |jump| {
+                    try self.replaceValue(jump, OpCode.Size(.jump), self.instructionPos());
+                    try self.enterScope(.local);
+                    try self.compileBlock(&[_]ast.Statement{});
+                    try self.writeOp(.jump, token);
+                    _ = try self.writeInt(OpCode.Size(.jump), SWITCH_END_HOLDER, token);
+                    try self.exitScope();
+                }
+
                 try replaceJumps(self.chunk.instructions.items[start..], SWITCH_END_HOLDER, self.instructionPos());
                 try self.writeOp(.pop, token);
             },

diff --git a/src/token.zig b/src/token.zig
@@ -92,7 +92,7 @@ pub const TokenType = enum {
     illegal,
 };
 
-pub const Keywords = std.ComptimeStringMap(TokenType, .{
+pub const Keywords = std.StaticStringMap(TokenType).initComptime(.{
     .{ "and", .@"and" },
     .{ "bough", .bough },
     .{ "break", .@"break" },

diff --git a/src/vm.test.zig b/src/vm.test.zig
@@ -59,8 +59,8 @@ pub const TestRunner = struct {
 
 var test_runner = TestRunner.init();
 pub fn initTestVm(source: []const u8, mod: *Module, debug: bool) !Vm {
-    const errWriter = std.io.getStdErr().writer();
     var bytecode = compileSource(source, mod) catch |err| {
+        const errWriter = std.io.getStdErr().writer();
         try mod.writeErrors(errWriter);
         return err;
     };
@@ -1414,6 +1414,7 @@ test "Switch" {
             \\     0: i = 0,
             \\     1: i = 1
             \\ }
+            \\ assert(i == 1, "{i} == 1");
             \\ i
             ,
             .value = 1.0,
@@ -1425,6 +1426,7 @@ test "Switch" {
             \\     0: i = 0,
             \\     1: i = 1
             \\ }
+            \\ assert(i == -1, "{i} == -1");
             \\ i
             ,
             .value = -1.0,
@@ -1436,6 +1438,7 @@ test "Switch" {
             \\     0: i = 0,
             \\     1: i = 1,
             \\ }
+            \\ assert(i == 1, "{i} == 1");
             \\ i
             ,
             .value = 1.0,
@@ -1448,6 +1451,7 @@ test "Switch" {
             \\     1: i = 1,
             \\     else: i = 5
             \\ }
+            \\ assert(i == 1, "{i} == 1");
             \\ i
             ,
             .value = 1.0,
@@ -1460,6 +1464,7 @@ test "Switch" {
             \\     1: i = 1,
             \\     else: i = 5
             \\ }
+            \\ assert(i == 5, "{i} == 5");
             \\ i
             ,
             .value = 5.0,
@@ -1472,6 +1477,7 @@ test "Switch" {
             \\     4,5,6,7: i = 4,
             \\     else: i = 5
             \\ }
+            \\ assert(i == 4, "{i} == 4");
             \\ i
             ,
             .value = 4.0,
@@ -1484,6 +1490,7 @@ test "Switch" {
             \\     4..7: i = 4,
             \\     else: i = 5
             \\ }
+            \\ assert(i == 4, "{i} == 4");
             \\ i
             ,
             .value = 4.0,
@@ -1496,6 +1503,7 @@ test "Switch" {
             \\     "two": i = 4,
             \\     "test": i = 5
             \\ }
+            \\ assert(i == 5, "{i} == 5");
             \\ i
             ,
             .value = 5.0,
@@ -1508,7 +1516,10 @@ test "Switch" {
         var vm = try initTestVm(case.input, &mod, false);
         defer vm.deinit();
         defer vm.bytecode.free(testing.allocator);
-        try vm.interpret();
+        vm.interpret() catch |err| {
+            vm.err.print(std.io.getStdErr().writer());
+            return err;
+        };
     }
 }
 
@@ -1534,6 +1545,9 @@ test "Externs and Subscribers" {
         const Listener = struct {
             pub fn onChange(name: []const u8, value: Value) void {
                 std.debug.print("\nListener \"{s}\"::{}\n", .{ name, value });
+                testing.expectEqual(case.value, value.number) catch {
+                    std.debug.print("Unexpected listener value", .{});
+                };
             }
         };
         try vm.setExtern("value", .{ .number = 2 });

diff --git a/src/vm.zig b/src/vm.zig
@@ -1057,10 +1057,11 @@ pub const Vm = struct {
 
     fn prongIsMatch(self: *Vm, capture: Value, case: Value) bool {
         _ = self;
-        return switch (case) {
+        const result = switch (case) {
             .range => |r| @as(i32, @intFromFloat(capture.number)) >= r.start and @as(i32, @intFromFloat(capture.number)) <= r.end,
             else => capture.eql(case),
         };
+        return result;
     }
 
     fn push(self: *Vm, value: Value) !void {