zig

blob 5fbb56b7 (42063B) - Raw

---

 const std = @import("std");
 const debug = std.debug;
 const warn = debug.warn;
 const build = std.build;
 const os = std.os;
 const StdIo = os.ChildProcess.StdIo;
 const Term = os.ChildProcess.Term;
 const Buffer = std.Buffer;
 const io = std.io;
 const mem = std.mem;
 const fmt = std.fmt;
 const ArrayList = std.ArrayList;
 const builtin = @import("builtin");
 const Mode = builtin.Mode;
 
 const compare_output = @import("compare_output.zig");
 const build_examples = @import("build_examples.zig");
 const compile_errors = @import("compile_errors.zig");
 const assemble_and_link = @import("assemble_and_link.zig");
 const runtime_safety = @import("runtime_safety.zig");
 const translate_c = @import("translate_c.zig");
 const gen_h = @import("gen_h.zig");
 
 const TestTarget = struct {
     os: builtin.Os,
     arch: builtin.Arch,
     environ: builtin.Environ,
 };
 
 const test_targets = []TestTarget {
     TestTarget {
         .os = builtin.Os.linux,
         .arch = builtin.Arch.x86_64,
         .environ = builtin.Environ.gnu,
     },
     TestTarget {
         .os = builtin.Os.macosx,
         .arch = builtin.Arch.x86_64,
         .environ = builtin.Environ.unknown,
     },
     TestTarget {
         .os = builtin.Os.windows,
         .arch = builtin.Arch.x86_64,
         .environ = builtin.Environ.msvc,
     },
 };
 
 const max_stdout_size = 1 * 1024 * 1024; // 1 MB
 
 pub fn addCompareOutputTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(CompareOutputContext) catch unreachable;
     *cases = CompareOutputContext {
         .b = b,
         .step = b.step("test-compare-output", "Run the compare output tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     compare_output.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addRuntimeSafetyTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(CompareOutputContext) catch unreachable;
     *cases = CompareOutputContext {
         .b = b,
         .step = b.step("test-runtime-safety", "Run the runtime safety tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     runtime_safety.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addCompileErrorTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(CompileErrorContext) catch unreachable;
     *cases = CompileErrorContext {
         .b = b,
         .step = b.step("test-compile-errors", "Run the compile error tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     compile_errors.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addBuildExampleTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(BuildExamplesContext) catch unreachable;
     *cases = BuildExamplesContext {
         .b = b,
         .step = b.step("test-build-examples", "Build the examples"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     build_examples.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addAssembleAndLinkTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(CompareOutputContext) catch unreachable;
     *cases = CompareOutputContext {
         .b = b,
         .step = b.step("test-asm-link", "Run the assemble and link tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     assemble_and_link.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addTranslateCTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(TranslateCContext) catch unreachable;
     *cases = TranslateCContext {
         .b = b,
         .step = b.step("test-translate-c", "Run the C transation tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     translate_c.addCases(cases);
 
     return cases.step;
 }
 
 pub fn addGenHTests(b: &build.Builder, test_filter: ?[]const u8) &build.Step {
     const cases = b.allocator.create(GenHContext) catch unreachable;
     *cases = GenHContext {
         .b = b,
         .step = b.step("test-gen-h", "Run the C header file generation tests"),
         .test_index = 0,
         .test_filter = test_filter,
     };
 
     gen_h.addCases(cases);
 
     return cases.step;
 }
 
 
 pub fn addPkgTests(b: &build.Builder, test_filter: ?[]const u8, root_src: []const u8,
     name:[] const u8, desc: []const u8, with_lldb: bool) &build.Step
 {
     const step = b.step(b.fmt("test-{}", name), desc);
     for (test_targets) |test_target| {
         const is_native = (test_target.os == builtin.os and test_target.arch == builtin.arch);
         for ([]Mode{Mode.Debug, Mode.ReleaseSafe, Mode.ReleaseFast, Mode.ReleaseSmall}) |mode| {
             for ([]bool{false, true}) |link_libc| {
                 if (link_libc and !is_native) {
                     // don't assume we have a cross-compiling libc set up
                     continue;
                 }
                 const these_tests = b.addTest(root_src);
                 these_tests.setNamePrefix(b.fmt("{}-{}-{}-{}-{} ", name, @tagName(test_target.os),
                     @tagName(test_target.arch), @tagName(mode), if (link_libc) "c" else "bare"));
                 these_tests.setFilter(test_filter);
                 these_tests.setBuildMode(mode);
                 if (!is_native) {
                     these_tests.setTarget(test_target.arch, test_target.os, test_target.environ);
                 }
                 if (link_libc) {
                     these_tests.linkSystemLibrary("c");
                 }
                 if (with_lldb) {
                     these_tests.setExecCmd([]?[]const u8{
                         "lldb", null, "-o", "run", "-o", "bt", "-o", "exit"});
                 }
                 step.dependOn(&these_tests.step);
             }
         }
     }
     return step;
 }
 
 pub const CompareOutputContext = struct {
     b: &build.Builder,
     step: &build.Step,
     test_index: usize,
     test_filter: ?[]const u8,
 
     const Special = enum {
         None,
         Asm,
         RuntimeSafety,
     };
 
     const TestCase = struct {
         name: []const u8,
         sources: ArrayList(SourceFile),
         expected_output: []const u8,
         link_libc: bool,
         special: Special,
         cli_args: []const []const u8,
 
         const SourceFile = struct {
             filename: []const u8,
             source: []const u8,
         };
 
         pub fn addSourceFile(self: &TestCase, filename: []const u8, source: []const u8) void {
             self.sources.append(SourceFile {
                 .filename = filename,
                 .source = source,
             }) catch unreachable;
         }
 
         pub fn setCommandLineArgs(self: &TestCase, args: []const []const u8) void {
             self.cli_args = args;
         }
     };
 
     const RunCompareOutputStep = struct {
         step: build.Step,
         context: &CompareOutputContext,
         exe_path: []const u8,
         name: []const u8,
         expected_output: []const u8,
         test_index: usize,
         cli_args: []const []const u8,
 
         pub fn create(context: &CompareOutputContext, exe_path: []const u8,
             name: []const u8, expected_output: []const u8,
             cli_args: []const []const u8) &RunCompareOutputStep
         {
             const allocator = context.b.allocator;
             const ptr = allocator.create(RunCompareOutputStep) catch unreachable;
             *ptr = RunCompareOutputStep {
                 .context = context,
                 .exe_path = exe_path,
                 .name = name,
                 .expected_output = expected_output,
                 .test_index = context.test_index,
                 .step = build.Step.init("RunCompareOutput", allocator, make),
                 .cli_args = cli_args,
             };
             context.test_index += 1;
             return ptr;
         }
 
         fn make(step: &build.Step) !void {
             const self = @fieldParentPtr(RunCompareOutputStep, "step", step);
             const b = self.context.b;
 
             const full_exe_path = b.pathFromRoot(self.exe_path);
             var args = ArrayList([]const u8).init(b.allocator);
             defer args.deinit();
 
             args.append(full_exe_path) catch unreachable;
             for (self.cli_args) |arg| {
                 args.append(arg) catch unreachable;
             }
 
             warn("Test {}/{} {}...", self.test_index+1, self.context.test_index, self.name);
 
             const child = os.ChildProcess.init(args.toSliceConst(), b.allocator) catch unreachable;
             defer child.deinit();
 
             child.stdin_behavior = StdIo.Ignore;
             child.stdout_behavior = StdIo.Pipe;
             child.stderr_behavior = StdIo.Pipe;
             child.env_map = &b.env_map;
 
             child.spawn() catch |err| debug.panic("Unable to spawn {}: {}\n", full_exe_path, @errorName(err));
 
             var stdout = Buffer.initNull(b.allocator);
             var stderr = Buffer.initNull(b.allocator);
 
             var stdout_file_in_stream = io.FileInStream.init(&??child.stdout);
             var stderr_file_in_stream = io.FileInStream.init(&??child.stderr);
 
             stdout_file_in_stream.stream.readAllBuffer(&stdout, max_stdout_size) catch unreachable;
             stderr_file_in_stream.stream.readAllBuffer(&stderr, max_stdout_size) catch unreachable;
 
             const term = child.wait() catch |err| {
                 debug.panic("Unable to spawn {}: {}\n", full_exe_path, @errorName(err));
             };
             switch (term) {
                 Term.Exited => |code| {
                     if (code != 0) {
                         warn("Process {} exited with error code {}\n", full_exe_path, code);
                         return error.TestFailed;
                     }
                 },
                 else => {
                     warn("Process {} terminated unexpectedly\n", full_exe_path);
                     return error.TestFailed;
                 },
             }
 
 
             if (!mem.eql(u8, self.expected_output, stdout.toSliceConst())) {
                 warn(
                     \\
                     \\========= Expected this output: =========
                     \\{}
                     \\================================================
                     \\{}
                     \\
                 , self.expected_output, stdout.toSliceConst());
                 return error.TestFailed;
             }
             warn("OK\n");
         }
     };
 
     const RuntimeSafetyRunStep = struct {
         step: build.Step,
         context: &CompareOutputContext,
         exe_path: []const u8,
         name: []const u8,
         test_index: usize,
 
         pub fn create(context: &CompareOutputContext, exe_path: []const u8,
             name: []const u8) &RuntimeSafetyRunStep
         {
             const allocator = context.b.allocator;
             const ptr = allocator.create(RuntimeSafetyRunStep) catch unreachable;
             *ptr = RuntimeSafetyRunStep {
                 .context = context,
                 .exe_path = exe_path,
                 .name = name,
                 .test_index = context.test_index,
                 .step = build.Step.init("RuntimeSafetyRun", allocator, make),
             };
             context.test_index += 1;
             return ptr;
         }
 
         fn make(step: &build.Step) !void {
             const self = @fieldParentPtr(RuntimeSafetyRunStep, "step", step);
             const b = self.context.b;
 
             const full_exe_path = b.pathFromRoot(self.exe_path);
 
             warn("Test {}/{} {}...", self.test_index+1, self.context.test_index, self.name);
 
             const child = os.ChildProcess.init([][]u8{full_exe_path}, b.allocator) catch unreachable;
             defer child.deinit();
 
             child.env_map = &b.env_map;
             child.stdin_behavior = StdIo.Ignore;
             child.stdout_behavior = StdIo.Ignore;
             child.stderr_behavior = StdIo.Ignore;
 
             const term = child.spawnAndWait() catch |err| {
                 debug.panic("Unable to spawn {}: {}\n", full_exe_path, @errorName(err));
             };
 
             const expected_exit_code: i32 = 126;
             switch (term) {
                 Term.Exited => |code| {
                     if (code != expected_exit_code) {
                         warn("\nProgram expected to exit with code {} " ++
                             "but exited with code {}\n", expected_exit_code, code);
                         return error.TestFailed;
                     }
                 },
                 Term.Signal => |sig| {
                     warn("\nProgram expected to exit with code {} " ++
                         "but instead signaled {}\n", expected_exit_code, sig);
                     return error.TestFailed;
                 },
                 else => {
                     warn("\nProgram expected to exit with code {}" ++
                         " but exited in an unexpected way\n", expected_exit_code);
                     return error.TestFailed;
                 },
             }
 
             warn("OK\n");
         }
     };
 
     pub fn createExtra(self: &CompareOutputContext, name: []const u8, source: []const u8,
         expected_output: []const u8, special: Special) TestCase
     {
         var tc = TestCase {
             .name = name,
             .sources = ArrayList(TestCase.SourceFile).init(self.b.allocator),
             .expected_output = expected_output,
             .link_libc = false,
             .special = special,
             .cli_args = []const []const u8{},
         };
         const root_src_name = if (special == Special.Asm) "source.s" else "source.zig";
         tc.addSourceFile(root_src_name, source);
         return tc;
     }
 
     pub fn create(self: &CompareOutputContext, name: []const u8, source: []const u8,
         expected_output: []const u8) TestCase
     {
         return createExtra(self, name, source, expected_output, Special.None);
     }
 
     pub fn addC(self: &CompareOutputContext, name: []const u8, source: []const u8, expected_output: []const u8) void {
         var tc = self.create(name, source, expected_output);
         tc.link_libc = true;
         self.addCase(tc);
     }
 
     pub fn add(self: &CompareOutputContext, name: []const u8, source: []const u8, expected_output: []const u8) void {
         const tc = self.create(name, source, expected_output);
         self.addCase(tc);
     }
 
     pub fn addAsm(self: &CompareOutputContext, name: []const u8, source: []const u8, expected_output: []const u8) void {
         const tc = self.createExtra(name, source, expected_output, Special.Asm);
         self.addCase(tc);
     }
 
     pub fn addRuntimeSafety(self: &CompareOutputContext, name: []const u8, source: []const u8) void {
         const tc = self.createExtra(name, source, undefined, Special.RuntimeSafety);
         self.addCase(tc);
     }
 
     pub fn addCase(self: &CompareOutputContext, case: &const TestCase) void {
         const b = self.b;
 
         const root_src = os.path.join(b.allocator, b.cache_root, case.sources.items[0].filename) catch unreachable;
 
         switch (case.special) {
             Special.Asm => {
                 const annotated_case_name = fmt.allocPrint(self.b.allocator, "assemble-and-link {}", case.name) catch unreachable;
                 if (self.test_filter) |filter| {
                     if (mem.indexOf(u8, annotated_case_name, filter) == null)
                         return;
                 }
 
                 const exe = b.addExecutable("test", null);
                 exe.addAssemblyFile(root_src);
 
                 for (case.sources.toSliceConst()) |src_file| {
                     const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
                     const write_src = b.addWriteFile(expanded_src_path, src_file.source);
                     exe.step.dependOn(&write_src.step);
                 }
 
                 const run_and_cmp_output = RunCompareOutputStep.create(self, exe.getOutputPath(), annotated_case_name,
                     case.expected_output, case.cli_args);
                 run_and_cmp_output.step.dependOn(&exe.step);
 
                 self.step.dependOn(&run_and_cmp_output.step);
             },
             Special.None => {
                 for ([]Mode{Mode.Debug, Mode.ReleaseSafe, Mode.ReleaseFast, Mode.ReleaseSmall}) |mode| {
                     const annotated_case_name = fmt.allocPrint(self.b.allocator, "{} {} ({})",
                         "compare-output", case.name, @tagName(mode)) catch unreachable;
                     if (self.test_filter) |filter| {
                         if (mem.indexOf(u8, annotated_case_name, filter) == null)
                             continue;
                     }
 
                     const exe = b.addExecutable("test", root_src);
                     exe.setBuildMode(mode);
                     if (case.link_libc) {
                         exe.linkSystemLibrary("c");
                     }
 
                     for (case.sources.toSliceConst()) |src_file| {
                         const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
                         const write_src = b.addWriteFile(expanded_src_path, src_file.source);
                         exe.step.dependOn(&write_src.step);
                     }
 
                     const run_and_cmp_output = RunCompareOutputStep.create(self, exe.getOutputPath(),
                         annotated_case_name, case.expected_output, case.cli_args);
                     run_and_cmp_output.step.dependOn(&exe.step);
 
                     self.step.dependOn(&run_and_cmp_output.step);
                 }
             },
             Special.RuntimeSafety => {
                 const annotated_case_name = fmt.allocPrint(self.b.allocator, "safety {}", case.name) catch unreachable;
                 if (self.test_filter) |filter| {
                     if (mem.indexOf(u8, annotated_case_name, filter) == null)
                         return;
                 }
 
                 const exe = b.addExecutable("test", root_src);
                 if (case.link_libc) {
                     exe.linkSystemLibrary("c");
                 }
 
                 for (case.sources.toSliceConst()) |src_file| {
                     const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
                     const write_src = b.addWriteFile(expanded_src_path, src_file.source);
                     exe.step.dependOn(&write_src.step);
                 }
 
                 const run_and_cmp_output = RuntimeSafetyRunStep.create(self, exe.getOutputPath(), annotated_case_name);
                 run_and_cmp_output.step.dependOn(&exe.step);
 
                 self.step.dependOn(&run_and_cmp_output.step);
             },
         }
     }
 };
 
 pub const CompileErrorContext = struct {
     b: &build.Builder,
     step: &build.Step,
     test_index: usize,
     test_filter: ?[]const u8,
 
     const TestCase = struct {
         name: []const u8,
         sources: ArrayList(SourceFile),
         expected_errors: ArrayList([]const u8),
         link_libc: bool,
         is_exe: bool,
 
         const SourceFile = struct {
             filename: []const u8,
             source: []const u8,
         };
 
         pub fn addSourceFile(self: &TestCase, filename: []const u8, source: []const u8) void {
             self.sources.append(SourceFile {
                 .filename = filename,
                 .source = source,
             }) catch unreachable;
         }
 
         pub fn addExpectedError(self: &TestCase, text: []const u8) void {
             self.expected_errors.append(text) catch unreachable;
         }
     };
 
     const CompileCmpOutputStep = struct {
         step: build.Step,
         context: &CompileErrorContext,
         name: []const u8,
         test_index: usize,
         case: &const TestCase,
         build_mode: Mode,
 
         pub fn create(context: &CompileErrorContext, name: []const u8,
             case: &const TestCase, build_mode: Mode) &CompileCmpOutputStep
         {
             const allocator = context.b.allocator;
             const ptr = allocator.create(CompileCmpOutputStep) catch unreachable;
             *ptr = CompileCmpOutputStep {
                 .step = build.Step.init("CompileCmpOutput", allocator, make),
                 .context = context,
                 .name = name,
                 .test_index = context.test_index,
                 .case = case,
                 .build_mode = build_mode,
             };
             context.test_index += 1;
             return ptr;
         }
 
         fn make(step: &build.Step) !void {
             const self = @fieldParentPtr(CompileCmpOutputStep, "step", step);
             const b = self.context.b;
 
             const root_src = os.path.join(b.allocator, b.cache_root, self.case.sources.items[0].filename) catch unreachable;
             const obj_path = os.path.join(b.allocator, b.cache_root, "test.o") catch unreachable;
 
             var zig_args = ArrayList([]const u8).init(b.allocator);
             zig_args.append(b.zig_exe) catch unreachable;
 
             zig_args.append(if (self.case.is_exe) "build-exe" else "build-obj") catch unreachable;
             zig_args.append(b.pathFromRoot(root_src)) catch unreachable;
 
             zig_args.append("--name") catch unreachable;
             zig_args.append("test") catch unreachable;
 
             zig_args.append("--output") catch unreachable;
             zig_args.append(b.pathFromRoot(obj_path)) catch unreachable;
 
             switch (self.build_mode) {
                 Mode.Debug => {},
                 Mode.ReleaseSafe => zig_args.append("--release-safe") catch unreachable,
                 Mode.ReleaseFast => zig_args.append("--release-fast") catch unreachable,
                 Mode.ReleaseSmall => zig_args.append("--release-small") catch unreachable,
             }
 
             warn("Test {}/{} {}...", self.test_index+1, self.context.test_index, self.name);
 
             if (b.verbose) {
                 printInvocation(zig_args.toSliceConst());
             }
 
             const child = os.ChildProcess.init(zig_args.toSliceConst(), b.allocator) catch unreachable;
             defer child.deinit();
 
             child.env_map = &b.env_map;
             child.stdin_behavior = StdIo.Ignore;
             child.stdout_behavior = StdIo.Pipe;
             child.stderr_behavior = StdIo.Pipe;
 
             child.spawn() catch |err| debug.panic("Unable to spawn {}: {}\n", zig_args.items[0], @errorName(err));
 
             var stdout_buf = Buffer.initNull(b.allocator);
             var stderr_buf = Buffer.initNull(b.allocator);
 
             var stdout_file_in_stream = io.FileInStream.init(&??child.stdout);
             var stderr_file_in_stream = io.FileInStream.init(&??child.stderr);
 
             stdout_file_in_stream.stream.readAllBuffer(&stdout_buf, max_stdout_size) catch unreachable;
             stderr_file_in_stream.stream.readAllBuffer(&stderr_buf, max_stdout_size) catch unreachable;
 
             const term = child.wait() catch |err| {
                 debug.panic("Unable to spawn {}: {}\n", zig_args.items[0], @errorName(err));
             };
             switch (term) {
                 Term.Exited => |code| {
                     if (code == 0) {
                         return error.CompilationIncorrectlySucceeded;
                     }
                 },
                 else => {
                     warn("Process {} terminated unexpectedly\n", b.zig_exe);
                     return error.TestFailed;
                 },
             }
 
 
             const stdout = stdout_buf.toSliceConst();
             const stderr = stderr_buf.toSliceConst();
 
             if (stdout.len != 0) {
                 warn(
                     \\
                     \\Expected empty stdout, instead found:
                     \\================================================
                     \\{}
                     \\================================================
                     \\
                 , stdout);
                 return error.TestFailed;
             }
 
             for (self.case.expected_errors.toSliceConst()) |expected_error| {
                 if (mem.indexOf(u8, stderr, expected_error) == null) {
                     warn(
                         \\
                         \\========= Expected this compile error: =========
                         \\{}
                         \\================================================
                         \\{}
                         \\
                     , expected_error, stderr);
                     return error.TestFailed;
                 }
             }
             warn("OK\n");
         }
     };
 
     fn printInvocation(args: []const []const u8) void {
         for (args) |arg| {
             warn("{} ", arg);
         }
         warn("\n");
     }
 
     pub fn create(self: &CompileErrorContext, name: []const u8, source: []const u8,
         expected_lines: ...) &TestCase
     {
         const tc = self.b.allocator.create(TestCase) catch unreachable;
         *tc = TestCase {
             .name = name,
             .sources = ArrayList(TestCase.SourceFile).init(self.b.allocator),
             .expected_errors = ArrayList([]const u8).init(self.b.allocator),
             .link_libc = false,
             .is_exe = false,
         };
         tc.addSourceFile(".tmp_source.zig", source);
         comptime var arg_i = 0;
         inline while (arg_i < expected_lines.len) : (arg_i += 1) {
             tc.addExpectedError(expected_lines[arg_i]);
         }
         return tc;
     }
 
     pub fn addC(self: &CompileErrorContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         var tc = self.create(name, source, expected_lines);
         tc.link_libc = true;
         self.addCase(tc);
     }
 
     pub fn addExe(self: &CompileErrorContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         var tc = self.create(name, source, expected_lines);
         tc.is_exe = true;
         self.addCase(tc);
     }
 
     pub fn add(self: &CompileErrorContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         const tc = self.create(name, source, expected_lines);
         self.addCase(tc);
     }
 
     pub fn addCase(self: &CompileErrorContext, case: &const TestCase) void {
         const b = self.b;
 
         for ([]Mode{Mode.Debug, Mode.ReleaseFast}) |mode| {
             const annotated_case_name = fmt.allocPrint(self.b.allocator, "compile-error {} ({})",
                 case.name, @tagName(mode)) catch unreachable;
             if (self.test_filter) |filter| {
                 if (mem.indexOf(u8, annotated_case_name, filter) == null)
                     continue;
             }
 
             const compile_and_cmp_errors = CompileCmpOutputStep.create(self, annotated_case_name, case, mode);
             self.step.dependOn(&compile_and_cmp_errors.step);
 
             for (case.sources.toSliceConst()) |src_file| {
                 const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
                 const write_src = b.addWriteFile(expanded_src_path, src_file.source);
                 compile_and_cmp_errors.step.dependOn(&write_src.step);
             }
         }
     }
 };
 
 pub const BuildExamplesContext = struct {
     b: &build.Builder,
     step: &build.Step,
     test_index: usize,
     test_filter: ?[]const u8,
 
     pub fn addC(self: &BuildExamplesContext, root_src: []const u8) void {
         self.addAllArgs(root_src, true);
     }
 
     pub fn add(self: &BuildExamplesContext, root_src: []const u8) void {
         self.addAllArgs(root_src, false);
     }
 
     pub fn addBuildFile(self: &BuildExamplesContext, build_file: []const u8) void {
         const b = self.b;
 
         const annotated_case_name = b.fmt("build {} (Debug)", build_file);
         if (self.test_filter) |filter| {
             if (mem.indexOf(u8, annotated_case_name, filter) == null)
                 return;
         }
 
         var zig_args = ArrayList([]const u8).init(b.allocator);
         const rel_zig_exe = os.path.relative(b.allocator, b.build_root, b.zig_exe) catch unreachable;
         zig_args.append(rel_zig_exe) catch unreachable;
         zig_args.append("build") catch unreachable;
 
         zig_args.append("--build-file") catch unreachable;
         zig_args.append(b.pathFromRoot(build_file)) catch unreachable;
 
         zig_args.append("test") catch unreachable;
 
         if (b.verbose) {
             zig_args.append("--verbose") catch unreachable;
         }
 
         const run_cmd = b.addCommand(null, b.env_map, zig_args.toSliceConst());
 
         const log_step = b.addLog("PASS {}\n", annotated_case_name);
         log_step.step.dependOn(&run_cmd.step);
 
         self.step.dependOn(&log_step.step);
     }
 
     pub fn addAllArgs(self: &BuildExamplesContext, root_src: []const u8, link_libc: bool) void {
         const b = self.b;
 
         for ([]Mode{Mode.Debug, Mode.ReleaseSafe, Mode.ReleaseFast, Mode.ReleaseSmall}) |mode| {
             const annotated_case_name = fmt.allocPrint(self.b.allocator, "build {} ({})",
                 root_src, @tagName(mode)) catch unreachable;
             if (self.test_filter) |filter| {
                 if (mem.indexOf(u8, annotated_case_name, filter) == null)
                     continue;
             }
 
             const exe = b.addExecutable("test", root_src);
             exe.setBuildMode(mode);
             if (link_libc) {
                 exe.linkSystemLibrary("c");
             }
 
             const log_step = b.addLog("PASS {}\n", annotated_case_name);
             log_step.step.dependOn(&exe.step);
 
             self.step.dependOn(&log_step.step);
         }
     }
 };
 
 pub const TranslateCContext = struct {
     b: &build.Builder,
     step: &build.Step,
     test_index: usize,
     test_filter: ?[]const u8,
 
     const TestCase = struct {
         name: []const u8,
         sources: ArrayList(SourceFile),
         expected_lines: ArrayList([]const u8),
         allow_warnings: bool,
 
         const SourceFile = struct {
             filename: []const u8,
             source: []const u8,
         };
 
         pub fn addSourceFile(self: &TestCase, filename: []const u8, source: []const u8) void {
             self.sources.append(SourceFile {
                 .filename = filename,
                 .source = source,
             }) catch unreachable;
         }
 
         pub fn addExpectedLine(self: &TestCase, text: []const u8) void {
             self.expected_lines.append(text) catch unreachable;
         }
     };
 
     const TranslateCCmpOutputStep = struct {
         step: build.Step,
         context: &TranslateCContext,
         name: []const u8,
         test_index: usize,
         case: &const TestCase,
 
         pub fn create(context: &TranslateCContext, name: []const u8, case: &const TestCase) &TranslateCCmpOutputStep {
             const allocator = context.b.allocator;
             const ptr = allocator.create(TranslateCCmpOutputStep) catch unreachable;
             *ptr = TranslateCCmpOutputStep {
                 .step = build.Step.init("ParseCCmpOutput", allocator, make),
                 .context = context,
                 .name = name,
                 .test_index = context.test_index,
                 .case = case,
             };
             context.test_index += 1;
             return ptr;
         }
 
         fn make(step: &build.Step) !void {
             const self = @fieldParentPtr(TranslateCCmpOutputStep, "step", step);
             const b = self.context.b;
 
             const root_src = os.path.join(b.allocator, b.cache_root, self.case.sources.items[0].filename) catch unreachable;
 
             var zig_args = ArrayList([]const u8).init(b.allocator);
             zig_args.append(b.zig_exe) catch unreachable;
 
             zig_args.append("translate-c") catch unreachable;
             zig_args.append(b.pathFromRoot(root_src)) catch unreachable;
 
             warn("Test {}/{} {}...", self.test_index+1, self.context.test_index, self.name);
 
             if (b.verbose) {
                 printInvocation(zig_args.toSliceConst());
             }
 
             const child = os.ChildProcess.init(zig_args.toSliceConst(), b.allocator) catch unreachable;
             defer child.deinit();
 
             child.env_map = &b.env_map;
             child.stdin_behavior = StdIo.Ignore;
             child.stdout_behavior = StdIo.Pipe;
             child.stderr_behavior = StdIo.Pipe;
 
             child.spawn() catch |err| debug.panic("Unable to spawn {}: {}\n", zig_args.toSliceConst()[0], @errorName(err));
 
             var stdout_buf = Buffer.initNull(b.allocator);
             var stderr_buf = Buffer.initNull(b.allocator);
 
             var stdout_file_in_stream = io.FileInStream.init(&??child.stdout);
             var stderr_file_in_stream = io.FileInStream.init(&??child.stderr);
 
             stdout_file_in_stream.stream.readAllBuffer(&stdout_buf, max_stdout_size) catch unreachable;
             stderr_file_in_stream.stream.readAllBuffer(&stderr_buf, max_stdout_size) catch unreachable;
 
             const term = child.wait() catch |err| {
                 debug.panic("Unable to spawn {}: {}\n", zig_args.toSliceConst()[0], @errorName(err));
             };
             switch (term) {
                 Term.Exited => |code| {
                     if (code != 0) {
                         warn("Compilation failed with exit code {}\n", code);
                         return error.TestFailed;
                     }
                 },
                 Term.Signal => |code| {
                     warn("Compilation failed with signal {}\n", code);
                     return error.TestFailed;
                 },
                 else => {
                     warn("Compilation terminated unexpectedly\n");
                     return error.TestFailed;
                 },
             }
 
             const stdout = stdout_buf.toSliceConst();
             const stderr = stderr_buf.toSliceConst();
 
             if (stderr.len != 0 and !self.case.allow_warnings) {
                 warn(
                     \\====== translate-c emitted warnings: =======
                     \\{}
                     \\============================================
                     \\
                 , stderr);
                 return error.TestFailed;
             }
 
             for (self.case.expected_lines.toSliceConst()) |expected_line| {
                 if (mem.indexOf(u8, stdout, expected_line) == null) {
                     warn(
                         \\
                         \\========= Expected this output: ================
                         \\{}
                         \\================================================
                         \\{}
                         \\
                     , expected_line, stdout);
                     return error.TestFailed;
                 }
             }
             warn("OK\n");
         }
     };
 
     fn printInvocation(args: []const []const u8) void {
         for (args) |arg| {
             warn("{} ", arg);
         }
         warn("\n");
     }
 
     pub fn create(self: &TranslateCContext, allow_warnings: bool, filename: []const u8, name: []const u8,
         source: []const u8, expected_lines: ...) &TestCase
     {
         const tc = self.b.allocator.create(TestCase) catch unreachable;
         *tc = TestCase {
             .name = name,
             .sources = ArrayList(TestCase.SourceFile).init(self.b.allocator),
             .expected_lines = ArrayList([]const u8).init(self.b.allocator),
             .allow_warnings = allow_warnings,
         };
         tc.addSourceFile(filename, source);
         comptime var arg_i = 0;
         inline while (arg_i < expected_lines.len) : (arg_i += 1) {
             tc.addExpectedLine(expected_lines[arg_i]);
         }
         return tc;
     }
 
     pub fn add(self: &TranslateCContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         const tc = self.create(false, "source.h", name, source, expected_lines);
         self.addCase(tc);
     }
 
     pub fn addC(self: &TranslateCContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         const tc = self.create(false, "source.c", name, source, expected_lines);
         self.addCase(tc);
     }
 
     pub fn addAllowWarnings(self: &TranslateCContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         const tc = self.create(true, "source.h", name, source, expected_lines);
         self.addCase(tc);
     }
 
     pub fn addCase(self: &TranslateCContext, case: &const TestCase) void {
         const b = self.b;
 
         const annotated_case_name = fmt.allocPrint(self.b.allocator, "translate-c {}", case.name) catch unreachable;
         if (self.test_filter) |filter| {
             if (mem.indexOf(u8, annotated_case_name, filter) == null)
                 return;
         }
 
         const translate_c_and_cmp = TranslateCCmpOutputStep.create(self, annotated_case_name, case);
         self.step.dependOn(&translate_c_and_cmp.step);
 
         for (case.sources.toSliceConst()) |src_file| {
             const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
             const write_src = b.addWriteFile(expanded_src_path, src_file.source);
             translate_c_and_cmp.step.dependOn(&write_src.step);
         }
     }
 };
 
 pub const GenHContext = struct {
     b: &build.Builder,
     step: &build.Step,
     test_index: usize,
     test_filter: ?[]const u8,
 
     const TestCase = struct {
         name: []const u8,
         sources: ArrayList(SourceFile),
         expected_lines: ArrayList([]const u8),
 
         const SourceFile = struct {
             filename: []const u8,
             source: []const u8,
         };
 
         pub fn addSourceFile(self: &TestCase, filename: []const u8, source: []const u8) void {
             self.sources.append(SourceFile {
                 .filename = filename,
                 .source = source,
             }) catch unreachable;
         }
 
         pub fn addExpectedLine(self: &TestCase, text: []const u8) void {
             self.expected_lines.append(text) catch unreachable;
         }
     };
 
     const GenHCmpOutputStep = struct {
         step: build.Step,
         context: &GenHContext,
         h_path: []const u8,
         name: []const u8,
         test_index: usize,
         case: &const TestCase,
 
         pub fn create(context: &GenHContext, h_path: []const u8, name: []const u8, case: &const TestCase) &GenHCmpOutputStep {
             const allocator = context.b.allocator;
             const ptr = allocator.create(GenHCmpOutputStep) catch unreachable;
             *ptr = GenHCmpOutputStep {
                 .step = build.Step.init("ParseCCmpOutput", allocator, make),
                 .context = context,
                 .h_path = h_path,
                 .name = name,
                 .test_index = context.test_index,
                 .case = case,
             };
             context.test_index += 1;
             return ptr;
         }
 
         fn make(step: &build.Step) !void {
             const self = @fieldParentPtr(GenHCmpOutputStep, "step", step);
             const b = self.context.b;
 
             warn("Test {}/{} {}...", self.test_index+1, self.context.test_index, self.name);
 
             const full_h_path = b.pathFromRoot(self.h_path);
             const actual_h = try io.readFileAlloc(b.allocator, full_h_path);
 
             for (self.case.expected_lines.toSliceConst()) |expected_line| {
                 if (mem.indexOf(u8, actual_h, expected_line) == null) {
                     warn(
                         \\
                         \\========= Expected this output: ================
                         \\{}
                         \\================================================
                         \\{}
                         \\
                     , expected_line, actual_h);
                     return error.TestFailed;
                 }
             }
             warn("OK\n");
         }
     };
 
     fn printInvocation(args: []const []const u8) void {
         for (args) |arg| {
             warn("{} ", arg);
         }
         warn("\n");
     }
 
     pub fn create(self: &GenHContext, filename: []const u8, name: []const u8,
         source: []const u8, expected_lines: ...) &TestCase
     {
         const tc = self.b.allocator.create(TestCase) catch unreachable;
         *tc = TestCase {
             .name = name,
             .sources = ArrayList(TestCase.SourceFile).init(self.b.allocator),
             .expected_lines = ArrayList([]const u8).init(self.b.allocator),
         };
         tc.addSourceFile(filename, source);
         comptime var arg_i = 0;
         inline while (arg_i < expected_lines.len) : (arg_i += 1) {
             tc.addExpectedLine(expected_lines[arg_i]);
         }
         return tc;
     }
 
     pub fn add(self: &GenHContext, name: []const u8, source: []const u8, expected_lines: ...) void {
         const tc = self.create("test.zig", name, source, expected_lines);
         self.addCase(tc);
     }
 
     pub fn addCase(self: &GenHContext, case: &const TestCase) void {
         const b = self.b;
         const root_src = os.path.join(b.allocator, b.cache_root, case.sources.items[0].filename) catch unreachable;
 
         const mode = builtin.Mode.Debug;
         const annotated_case_name = fmt.allocPrint(self.b.allocator, "gen-h {} ({})", case.name, @tagName(mode)) catch unreachable;
         if (self.test_filter) |filter| {
             if (mem.indexOf(u8, annotated_case_name, filter) == null)
                 return;
         }
 
         const obj = b.addObject("test", root_src);
         obj.setBuildMode(mode);
 
         for (case.sources.toSliceConst()) |src_file| {
             const expanded_src_path = os.path.join(b.allocator, b.cache_root, src_file.filename) catch unreachable;
             const write_src = b.addWriteFile(expanded_src_path, src_file.source);
             obj.step.dependOn(&write_src.step);
         }
 
         const cmp_h = GenHCmpOutputStep.create(self, obj.getOutputHPath(), annotated_case_name, case);
         cmp_h.step.dependOn(&obj.step);
 
         self.step.dependOn(&cmp_h.step);
     }
 };