Add Zig implementation

texttests/config.gr

@@ -14,6 +14,9 @@ diff_program:meld
 # Settings for the c (cmocka) version
 #executable:${TEXTTEST_HOME}/c_cmocka/cmake-build-debug/main
 
+# Settings for the zig version
+#executable:${TEXTTEST_HOME}/zig/zig-out/bin/zig
+
 # Settings for the Java version using Gradle wrapped in a python script
 #executable:${TEXTTEST_HOME}/Java/texttest_rig.py
 #interpreter:python

zig/.gitignore

@@ -0,0 +1,13 @@
+# Created by https://www.toptal.com/developers/gitignore/api/zig
+# Edit at https://www.toptal.com/developers/gitignore?templates=zig
+
+### zig ###
+# Zig programming language
+
+zig-cache/
+zig-out/
+build/
+build-*/
+docgen_tmp/
+
+# End of https://www.toptal.com/developers/gitignore/api/zig

zig/README.md

@@ -0,0 +1,34 @@
+# Gilded Rose starting position in Zig
+
+I assume you have [installed](https://ziglang.org/learn/getting-started/#installing-zig) `zig` on your system.
+
+## Run unit tests from the command line
+
+```sh
+$ zig build test
+```
+
+## Run the TextTest fixture on the command line
+
+Build and install the executable
+
+```sh
+$ zig build
+```
+
+Execute it on the command line with an argument for the number of days:
+
+```sh
+$ ./zig/zig-out/bin/zig 10
+```
+
+## Run the TextTest approval test that comes with this project
+
+There are instructions in the [TextTest Readme](../texttests/README.md) for setting up TextTest.
+You will need to specify the executable in [config.gr](../texttests/config.gr).
+Uncomment this line to use it:
+
+```
+#executable:${TEXTTEST_HOME}/zig/zig-out/bin/zig
+```
+

zig/build.zig

@@ -0,0 +1,68 @@
+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(.{});
+
+    // 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 exe = b.addExecutable(.{
+        .name = "zig",
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    // 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 = b.path("src/gilded_rose.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const run_lib_unit_tests = b.addRunArtifact(lib_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);
+}

zig/src/gilded_rose.zig

@@ -0,0 +1,79 @@
+const std = @import("std");
+
+pub const Item = struct {
+    name: []const u8,
+    sell_in: i32,
+    quality: i32,
+
+    pub fn init(name: []const u8, sell_in: i32, quality: i32) Item {
+        return Item{
+            .name = name,
+            .sell_in = sell_in,
+            .quality = quality,
+        };
+    }
+};
+
+pub const GildedRose = struct {
+    items: []Item,
+
+    pub fn init(items: []Item) GildedRose {
+        return GildedRose{ .items = items };
+    }
+
+    pub fn updateQuality(self: *GildedRose) []Item {
+        for (0..self.items.len) |i| {
+            if (!std.mem.eql(u8, self.items[i].name, "Aged Brie") and !std.mem.eql(u8, self.items[i].name, "Backstage passes to a TAFKAL80ETC concert")) {
+                if (self.items[i].quality > 0) {
+                    if (!std.mem.eql(u8, self.items[i].name, "Sulfuras, Hand of Ragnaros")) {
+                        self.items[i].quality = self.items[i].quality - 1;
+                    }
+                }
+            } else {
+                if (self.items[i].quality < 50) {
+                    self.items[i].quality = self.items[i].quality + 1;
+                    if (std.mem.eql(u8, self.items[i].name, "Backstage passes to a TAFKAL80ETC concert")) {
+                        if (self.items[i].sell_in < 11) {
+                            if (self.items[i].quality < 50) {
+                                self.items[i].quality = self.items[i].quality + 1;
+                            }
+                        }
+                        if (self.items[i].sell_in < 6) {
+                            if (self.items[i].quality < 50) {
+                                self.items[i].quality = self.items[i].quality + 1;
+                            }
+                        }
+                    }
+                }
+            }
+            if (!std.mem.eql(u8, self.items[i].name, "Sulfuras, Hand of Ragnaros")) {
+                self.items[i].sell_in = self.items[i].sell_in - 1;
+            }
+            if (self.items[i].sell_in < 0) {
+                if (!std.mem.eql(u8, self.items[i].name, "Aged Brie")) {
+                    if (!std.mem.eql(u8, self.items[i].name, "Backstage passes to a TAFKAL80ETC concert")) {
+                        if (self.items[i].quality > 0) {
+                            if (!std.mem.eql(u8, self.items[i].name, "Sulfuras, Hand of Ragnaros")) {
+                                self.items[i].quality = self.items[i].quality - 1;
+                            }
+                        }
+                    } else {
+                        self.items[i].quality = self.items[i].quality - self.items[i].quality;
+                    }
+                } else {
+                    if (self.items[i].quality < 50) {
+                        self.items[i].quality = self.items[i].quality + 1;
+                    }
+                }
+            }
+        }
+        return self.items;
+    }
+};
+
+test "updateQuality" {
+    var items = [_]Item{Item.init("foo", 0, 0)};
+    var app = GildedRose.init(&items);
+    _ = app.updateQuality();
+    try std.testing.expectEqualStrings("fixme", items[0].name);
+}

zig/src/main.zig

@@ -0,0 +1,43 @@
+const std = @import("std");
+const gilded_rose = @import("gilded_rose.zig");
+const Item = gilded_rose.Item;
+const GildedRose = gilded_rose.GildedRose;
+
+pub fn main() !void {
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    const args = try std.process.argsAlloc(allocator);
+    var days: u8 = 2;
+    if (args.len >= 2) {
+        days = try std.fmt.parseInt(u8, args[1], 10);
+    }
+
+    var items = [_]Item{
+        Item.init("+5 Dexterity Vest", 10, 20),
+        Item.init("Aged Brie", 2, 0),
+        Item.init("Elixir of the Mongoose", 5, 7),
+        Item.init("Sulfuras, Hand of Ragnaros", 0, 80),
+        Item.init("Sulfuras, Hand of Ragnaros", -1, 80),
+        Item.init("Backstage passes to a TAFKAL80ETC concert", 15, 20),
+        Item.init("Backstage passes to a TAFKAL80ETC concert", 10, 49),
+        Item.init("Backstage passes to a TAFKAL80ETC concert", 5, 49),
+        // this Conjured item doesn't yet work properly
+        Item.init("Conjured Mana Cake", 3, 6),
+    };
+    var app = GildedRose.init(&items);
+
+    const stdout = std.io.getStdOut().writer();
+    try stdout.print("OMGHAI!\n", .{});
+
+    for (0..days + 1) |day| {
+        try stdout.print("-------- day {d} --------\n", .{day});
+        try stdout.print("name, sellIn, quality\n", .{});
+        for (items) |item| {
+            try stdout.print("{s}, {d}, {d}\n", .{ item.name, item.sell_in, item.quality });
+        }
+        try stdout.print("\n", .{});
+        _ = app.updateQuality();
+    }
+}