diff --git a/build.zig b/build.zig index e7323ac..b63417e 100644 --- a/build.zig +++ b/build.zig @@ -1,11 +1,33 @@ const std = @import("std"); +// Although this function looks imperative, note that its job is to +// declaratively construct a build graph that will be executed by an external +// runner. pub fn build(b: *std.Build) void { + // Standard target options allows the person running `zig build` to choose + // what target to build for. Here we do not override the defaults, which + // means any target is allowed, and the default is native. Other options + // for restricting supported target set are available. const target = b.standardTargetOptions(.{}); - const optimize = b.standardOptimizeOption(.{}); - const opts = .{ .target = target, .optimize = optimize }; - const json = b.dependency("json", opts).module("json"); + // Standard optimization options allow the person running `zig build` to select + // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not + // set a preferred release mode, allowing the user to decide how to optimize. + const optimize = b.standardOptimizeOption(.{}); + + const lib = b.addStaticLibrary(.{ + .name = "learnzig", + // In this case the main source file is merely a path, however, in more + // complicated build scripts, this could be a generated file. + .root_source_file = .{ .path = "src/root.zig" }, + .target = target, + .optimize = optimize, + }); + + // This declares intent for the library to be installed into the standard + // location when the user invokes the "install" step (the default step when + // running `zig build`). + b.installArtifact(lib); const exe = b.addExecutable(.{ .name = "learnzig", @@ -13,24 +35,57 @@ pub fn build(b: *std.Build) void { .target = target, .optimize = optimize, }); - exe.root_module.addImport("json", json); + + // This declares intent for the executable to be installed into the + // standard location when the user invokes the "install" step (the default + // step when running `zig build`). b.installArtifact(exe); + // This *creates* a Run step in the build graph, to be executed when another + // step is evaluated that depends on it. The next line below will establish + // such a dependency. const run_cmd = b.addRunArtifact(exe); + + // By making the run step depend on the install step, it will be run from the + // installation directory rather than directly from within the cache directory. + // This is not necessary, however, if the application depends on other installed + // files, this ensures they will be present and in the expected location. run_cmd.step.dependOn(b.getInstallStep()); + + // This allows the user to pass arguments to the application in the build + // command itself, like this: `zig build run -- arg1 arg2 etc` if (b.args) |args| { run_cmd.addArgs(args); } + // This creates a build step. It will be visible in the `zig build --help` menu, + // and can be selected like this: `zig build run` + // This will evaluate the `run` step rather than the default, which is "install". const run_step = b.step("run", "Run the app"); run_step.dependOn(&run_cmd.step); + // Creates a step for unit testing. This only builds the test executable + // but does not run it. + const lib_unit_tests = b.addTest(.{ + .root_source_file = .{ .path = "src/root.zig" }, + .target = target, + .optimize = optimize, + }); + + const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests); + const exe_unit_tests = b.addTest(.{ .root_source_file = .{ .path = "src/main.zig" }, .target = target, .optimize = optimize, }); + const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests); + + // Similar to creating the run step earlier, this exposes a `test` step to + // the `zig build --help` menu, providing a way for the user to request + // running the unit tests. const test_step = b.step("test", "Run unit tests"); + test_step.dependOn(&run_lib_unit_tests.step); test_step.dependOn(&run_exe_unit_tests.step); } diff --git a/build.zig.zon b/build.zig.zon index 33785a7..8814bdd 100644 --- a/build.zig.zon +++ b/build.zig.zon @@ -15,11 +15,37 @@ // Once all dependencies are fetched, `zig build` no longer requires // internet connectivity. .dependencies = .{ - .json = .{ - .url = "git+https://github.com/getty-zig/json.git#main", - .hash = "1220a6a7706fa609ce63e2bf61812515f6ab45273397ca591f925a32e7e507cb7cec", - }, + // See `zig fetch --save ` for a command-line interface for adding dependencies. + //.example = .{ + // // When updating this field to a new URL, be sure to delete the corresponding + // // `hash`, otherwise you are communicating that you expect to find the old hash at + // // the new URL. + // .url = "https://example.com/foo.tar.gz", + // + // // This is computed from the file contents of the directory of files that is + // // obtained after fetching `url` and applying the inclusion rules given by + // // `paths`. + // // + // // This field is the source of truth; packages do not come from a `url`; they + // // come from a `hash`. `url` is just one of many possible mirrors for how to + // // obtain a package matching this `hash`. + // // + // // Uses the [multihash](https://multiformats.io/multihash/) format. + // .hash = "...", + // + // // When this is provided, the package is found in a directory relative to the + // // build root. In this case the package's hash is irrelevant and therefore not + // // computed. This field and `url` are mutually exclusive. + // .path = "foo", + //}, }, + + // Specifies the set of files and directories that are included in this package. + // Only files and directories listed here are included in the `hash` that + // is computed for this package. + // Paths are relative to the build root. Use the empty string (`""`) to refer to + // the build root itself. + // A directory listed here means that all files within, recursively, are included. .paths = .{ // This makes *all* files, recursively, included in this package. It is generally // better to explicitly list the files and directories instead, to insure that diff --git a/src/main.zig b/src/main.zig index 6dbde9b..c8a3f67 100644 --- a/src/main.zig +++ b/src/main.zig @@ -1,80 +1,24 @@ const std = @import("std"); -const json = @import("json"); - -fn concat(ally: std.mem.Allocator, u: []const u8, v: []const u8) ![]const u8 { - const res = try ally.alloc(u8, u.len + v.len); - @memcpy(res[0..u.len], u); - @memcpy(res[u.len .. u.len + v.len], v); - return res; -} - -const Shape = union(enum) { - rect: struct { w: f32, h: f32 }, - square: struct { s: f32 }, - circle: struct { r: f32 }, -}; - -fn show(shape: Shape) void { - var gpa = std.heap.GeneralPurposeAllocator(.{}){}; - const all = gpa.allocator(); - const text = json.toSlice(all, shape) catch unreachable; - defer all.free(text); - std.debug.print("shape: {s}\n", .{text}); - // switch (shape) { - // Shape.rect => |r| std.debug.print("rect: {} x {}\n", .{ r.w, r.h }), - // Shape.square => |s| std.debug.print("square: {}\n", .{s.s}), - // Shape.circle => |c| std.debug.print("circle: {}\n", .{c.r}), - // } -} - -const Point = struct { - x: i32, - y: i32, -}; pub fn main() !void { - var big_buf: [1 << 20]u8 = undefined; // 1 MB - var fixed = std.heap.FixedBufferAllocator.init(&big_buf); - const ally = fixed.allocator(); + // Prints to stderr (it's a shortcut based on `std.io.getStdErr()`) + std.debug.print("All your {s} are belong to us.\n", .{"codebase"}); - var s: Shape = Shape{ .circle = .{ .r = 99 } }; - show(s); - s = Shape{ .rect = .{ .w = 1, .h = 2 } }; - show(s); + // stdout is for the actual output of your application, for example if you + // are implementing gzip, then only the compressed bytes should be sent to + // stdout, not any debugging messages. + const stdout_file = std.io.getStdOut().writer(); + var bw = std.io.bufferedWriter(stdout_file); + const stdout = bw.writer(); - const val = Point{ .x = 1, .y = 2 }; - const ser = try json.toSlice(ally, val); - defer ally.free(ser); + try stdout.print("Run `zig build test` to run the tests.\n", .{}); - std.debug.print("{s}\n", .{ser}); - - const deser = try json.fromSlice(ally, Point, ser); - std.debug.print("{any}\n", .{deser}); - - var hash_map = std.StringArrayHashMap([]const u8).init(ally); - defer hash_map.deinit(); - - try hash_map.put("foo", "bar"); - try hash_map.put("fizz", "buzz"); - try hash_map.put("qux", "quxx"); - - const x = try concat(ally, hash_map.get("fizz").?, hash_map.get("foo").?); - defer ally.free(x); - - std.debug.print("x={s}\n", .{x}); - - var iter = hash_map.iterator(); - while (iter.next()) |it| { - std.debug.print("{s} {s}\n", .{ it.key_ptr.*, it.value_ptr.* }); - } + try bw.flush(); // don't forget to flush! } -test concat { - const x = "hello"; - const y = "world"; - - const z = try concat(std.testing.allocator, x, y); - defer std.testing.allocator.free(z); - - try std.testing.expectEqualStrings(z, "helloworld"); +test "simple test" { + var list = std.ArrayList(i32).init(std.testing.allocator); + defer list.deinit(); // try commenting this out and see if zig detects the memory leak! + try list.append(42); + try std.testing.expectEqual(@as(i32, 42), list.pop()); } diff --git a/src/root.zig b/src/root.zig new file mode 100644 index 0000000..ecfeade --- /dev/null +++ b/src/root.zig @@ -0,0 +1,10 @@ +const std = @import("std"); +const testing = std.testing; + +export fn add(a: i32, b: i32) i32 { + return a + b; +} + +test "basic add functionality" { + try testing.expect(add(3, 7) == 10); +}