4 files changed, 57 insertions(+), 52 deletions(-)

M README.md
A src/README.md
M src/bare.zig
M src/test.zig

@@ 41,24 41,26 @@ const x = Bar{
     .c = .{ .y = "hello" },
 };
 
-var buf: [12]u8 = undefined;
-var fbs = io.fixedBufferStream(&buf);
+test "example" {
+    var buf: [12]u8 = undefined;
+    var fbs = io.fixedBufferStream(&buf);
 
-var reader = fbs.reader();
-var writer = fbs.writer();
+    var reader = fbs.reader();
+    var writer = fbs.writer();
 
-var e = encoder(writer);
-try e.encode(x);
+    var e = encoder(writer);
+    try e.encode(x);
 
-try fbs.seekTo(0);
+    try fbs.seekTo(0);
 
-var d = decoder(allocator, reader);
-defer d.deinit();
+    var d = decoder(std.testing.allocator, reader);
+    defer d.deinit();
 
-const y = try d.decode(Bar);
+    const y = try d.decode(Bar);
 
-std.log.info("x: {}", .{x});
-std.log.info("y: {}", .{y});
+    std.log.info("x: {}", .{x});
+    std.log.info("y: {}", .{y});
+}
 ```
 
 Hash maps and slices require allocation;

@@ 0,0 1,1 @@
+../README.md<
\ No newline at end of file

@@ 511,42 511,3 @@ test "round trip union with void member" {
     const res = try d.decode(U);
     try std.testing.expectEqual(res, U{ .Hello = 123 });
 }
-
-test "README example" {
-    const Foo = union(enum) {
-        x: u64,
-        y: []const u8,
-        z: void,
-    };
-
-    const Bar = struct {
-        a: f32,
-        b: u8,
-        c: Foo,
-    };
-
-    const x = Bar{
-        .a = 3.14,
-        .b = 2,
-        .c = .{ .y = "hello" },
-    };
-
-    var buf: [12]u8 = undefined;
-    var fbs = io.fixedBufferStream(&buf);
-
-    var reader = fbs.reader();
-    var writer = fbs.writer();
-
-    var e = encoder(writer);
-    try e.encode(x);
-
-    try fbs.seekTo(0);
-
-    var d = decoder(std.testing.allocator, reader);
-    defer d.deinit();
-
-    const y = try d.decode(Bar);
-
-    std.log.info("x: {}", .{x});
-    std.log.info("y: {}", .{y});
-}

@@ 964,7 964,29 @@ fn testCompileError(comptime code: []const u8, comptime expected_error: []const 
     defer gpa.allocator().free(stderr);
     const term = try proc.wait();
     try checkErrorMessage(stderr, expected_error);
-    try expectEqual(term.Exited, 1);
+    try expectEqual(@as(u8, 1), term.Exited);
+}
+
+fn runZigTestOnCodeString(comptime code: []const u8) !void {
+    var buf: [1024]u8 = undefined;
+    const fname = try std.fmt.bufPrint(&buf, "/tmp/zig-bare-test-{d}.zig", .{test_file_seq});
+    test_file_seq += 1;
+    var cwd = fs.cwd();
+    try cwd.copyFile("src/bare.zig", cwd, "/tmp/zig-bare.zig", .{});
+    var tmpfile = try cwd.createFile(fname, .{ .read = true, .truncate = true });
+    defer tmpfile.close();
+    _ = try tmpfile.write(boilerplate);
+    _ = try tmpfile.write(code);
+    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+    var proc = std.ChildProcess.init(&[_][]const u8{ "zig", "test", fname, "-fno-emit-bin" }, gpa.allocator());
+    proc.stderr_behavior = .Pipe;
+    proc.stdout_behavior = .Pipe;
+    try proc.spawn();
+    const stderr = try proc.stderr.?.reader().readAllAlloc(gpa.allocator(), 0x1000);
+    defer gpa.allocator().free(stderr);
+    std.debug.print("??? {s}\n", .{stderr});
+    const term = try proc.wait();
+    try expectEqual(@as(u8, 0), term.Exited);
 }
 
 fn checkErrorMessage(haystack: []const u8, message: []const u8) !void {


@@ 973,3 995,22 @@ fn checkErrorMessage(haystack: []const u8, message: []const u8) !void {
     const errorslice = haystack[idx + errorstart.len ..];
     try testing.expectStringStartsWith(errorslice, message);
 }
+
+test "README example" {
+    @setEvalBranchQuota(1000000);
+    const readme_text = @embedFile("README.md");
+    const needle_start = "```zig";
+    const needle_end = "```";
+    const zig_code_start = comptime std.mem.indexOf(u8, readme_text, needle_start);
+
+    if (zig_code_start) |start| {
+        const rest = readme_text[start + needle_start.len ..];
+        const zig_code_end = comptime std.mem.indexOf(u8, rest, needle_end);
+
+        if (zig_code_end) |end| {
+            const zig_code = rest[0..end];
+
+            try runZigTestOnCodeString(zig_code);
+        }
+    }
+}