Moves files to file-global struct layout.

1 files changed, 57 insertions, 0 deletions

diff --git a/lib/std/build/CheckFileStep.zig b/lib/std/build/CheckFileStep.zig
new file mode 100644
index 0000000000..5422439472
--- /dev/null
+++ b/lib/std/build/CheckFileStep.zig
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2015-2021 Zig Contributors
+// This file is part of [zig](https://ziglang.org/), which is MIT licensed.
+// The MIT license requires this copyright notice to be included in all copies
+// and substantial portions of the software.
+const std = @import("../std.zig");
+const build = std.build;
+const Step = build.Step;
+const Builder = build.Builder;
+const fs = std.fs;
+const mem = std.mem;
+const warn = std.debug.warn;
+
+const CheckFileStep = @This();
+
+step: Step,
+builder: *Builder,
+expected_matches: []const []const u8,
+source: build.FileSource,
+max_bytes: usize = 20 * 1024 * 1024,
+
+pub fn create(
+    builder: *Builder,
+    source: build.FileSource,
+    expected_matches: []const []const u8,
+) *CheckFileStep {
+    const self = builder.allocator.create(CheckFileStep) catch unreachable;
+    self.* = CheckFileStep{
+        .builder = builder,
+        .step = Step.init(.CheckFile, "CheckFile", builder.allocator, make),
+        .source = source.dupe(builder),
+        .expected_matches = builder.dupeStrings(expected_matches),
+    };
+    self.source.addStepDependencies(&self.step);
+    return self;
+}
+
+fn make(step: *Step) !void {
+    const self = @fieldParentPtr(CheckFileStep, "step", step);
+
+    const src_path = self.source.getPath(self.builder);
+    const contents = try fs.cwd().readFileAlloc(self.builder.allocator, src_path, self.max_bytes);
+
+    for (self.expected_matches) |expected_match| {
+        if (mem.indexOf(u8, contents, expected_match) == null) {
+            warn(
+                \\
+                \\========= Expected to find: ===================
+                \\{s}
+                \\========= But file does not contain it: =======
+                \\{s}
+                \\
+            , .{ expected_match, contents });
+            return error.TestFailed;
+        }
+    }
+}