feat: add mockInputJson helper, rearrange for multiple tests

.github/workflows/ci.yml

@@ -22,5 +22,6 @@ jobs:
       - name: Test example
         run: |
           # this is configured by the `xtp.toml` in the root
-          xtp plugin test
+          xtp plugin test --path examples/basic
+          xtp plugin test --path examples/json
       

build.zig

@@ -23,15 +23,27 @@ pub fn build(b: *std.Build) void {
 
     var basic_test = b.addExecutable(.{
         .name = "basic-test",
-        .root_source_file = b.path("examples/basic.zig"),
+        .root_source_file = b.path("examples/basic/basic.zig"),
         .target = target,
         .optimize = optimize,
     });
     basic_test.rdynamic = true;
     basic_test.entry = .disabled; // or, add an empty `pub fn main() void {}` in your code
     basic_test.root_module.addImport("xtp-test", xtp_test_module);
-
     b.installArtifact(basic_test);
     const basic_test_step = b.step("basic_test", "Build basic_test");
     basic_test_step.dependOn(b.getInstallStep());
+
+    var json_test = b.addExecutable(.{
+        .name = "json-test",
+        .root_source_file = b.path("examples/json/json.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+    json_test.rdynamic = true;
+    json_test.entry = .disabled; // or, add an empty `pub fn main() void {}` in your code
+    json_test.root_module.addImport("xtp-test", xtp_test_module);
+    b.installArtifact(json_test);
+    const json_test_step = b.step("json_test", "Build json_test");
+    json_test_step.dependOn(b.getInstallStep());
 }

build.zig.zon

@@ -2,7 +2,7 @@
     .name = "xtp-test",
     // This is a [Semantic Version](https://semver.org/).
     // In a future version of Zig it will be used for package deduplication.
-    .version = "0.0.0",
+    .version = "0.1.0",
 
     // This field is optional.
     // This is currently advisory only; Zig does not yet do anything

xtp.toml → examples/basic/xtp.toml

@@ -10,4 +10,4 @@ mock_input = { data = "this is my mock input data" }
 name = "basic - file input"
 build = "zig build basic_test"
 with = "zig-out/bin/basic-test.wasm"
-mock_input = { file = "examples/basic.zig" }
+mock_input = { file = "examples/basic/basic.zig" }

examples/json/json.zig

@@ -0,0 +1,18 @@
+const std = @import("std");
+const Test = @import("xtp-test").Test;
+
+const CountVowel = struct {
+    total: u32,
+    count: u32,
+    vowels: []const u8,
+};
+
+export fn @"test"() i32 {
+    const xtp_test = Test.init(std.heap.wasm_allocator);
+    const input = xtp_test.mockInputJson(CountVowel, null) catch unreachable;
+    const example = CountVowel{ .total = 2, .count = 1, .vowels = "aeiouAEIOU" };
+    xtp_test.assertEq("json works (consistent .count)", input.count, example.count);
+    xtp_test.assertEq("json works (consistent .total)", input.total, example.total);
+    xtp_test.assert("json works (consistent .vowels)", std.mem.eql(u8, input.vowels, example.vowels), "expected count and vowels fields to match after conversion");
+    return 0;
+}

examples/json/xtp.toml

@@ -0,0 +1,7 @@
+bin = "https://raw.githubusercontent.com/extism/extism/main/wasm/code.wasm"
+
+[[test]]
+name = "json"
+build = "zig build json_test"
+with = "zig-out/bin/json-test.wasm"
+mock_input = { data = '{ "count": 1, "total": 2, "vowels": "aeiouAEIOU" }' }

src/main.zig

@@ -6,6 +6,21 @@ const harness = @import("harness.zig");
 
 const FORMAT_FAILED = "-- test runner failed to format reason --";
 
+pub fn Json(comptime T: type) type {
+    return struct {
+        parsed: std.json.Parsed(T),
+        slice: []const u8,
+
+        pub fn value(self: @This()) T {
+            return self.parsed.value;
+        }
+
+        pub fn deinit(self: @This()) void {
+            self.parsed.deinit();
+        }
+    };
+}
+
 pub const Test = struct {
     plugin: Plugin,
 
@@ -29,6 +44,15 @@ pub const Test = struct {
         }
     }
 
+    pub fn mockInputJson(self: Test, comptime T: type, options: ?std.json.ParseOptions) !T {
+        const default_opts = .{ .allocate = .alloc_always, .ignore_unknown_fields = true };
+        const bytes = self.mockInput() orelse return error.NoMockInput;
+        const out = try std.json.parseFromSlice(T, self.plugin.allocator, bytes, options orelse default_opts);
+        const FromJson = Json(T);
+        const input = FromJson{ .parsed = out, .slice = bytes };
+        return input.parsed.value;
+    }
+
     // Call a function from the Extism plugin being tested, passing input and returning its output.
     pub fn call(self: Test, func_name: []const u8, input: []const u8) ![]const u8 {
         const func_mem = self.plugin.allocateBytes(func_name);