make sure cli/tui are handled by zig build test and augment coverage step for multiple modules

build.zig

@@ -32,7 +32,7 @@ pub fn build(b: *std.Build) void {
         },
     });
 
-    // Shared TUI imports (used by the TUI module and its tests)
+    // Shared imports for TUI and CLI modules
     const tui_imports: []const std.Build.Module.Import = &.{
         .{ .name = "zfin", .module = mod },
         .{ .name = "srf", .module = srf_mod },
@@ -40,13 +40,18 @@ pub fn build(b: *std.Build) void {
         .{ .name = "z2d", .module = z2d_dep.module("z2d") },
     };
 
-    // TUI module (imported by the unified binary)
     const tui_mod = b.addModule("tui", .{
         .root_source_file = b.path("src/tui/main.zig"),
         .target = target,
         .imports = tui_imports,
     });
 
+    const cli_imports: []const std.Build.Module.Import = &.{
+        .{ .name = "zfin", .module = mod },
+        .{ .name = "srf", .module = srf_mod },
+        .{ .name = "tui", .module = tui_mod },
+    };
+
     // Unified executable (CLI + TUI in one binary)
     const exe = b.addExecutable(.{
         .name = "zfin",
@@ -54,11 +59,7 @@ pub fn build(b: *std.Build) void {
             .root_source_file = b.path("src/cli/main.zig"),
             .target = target,
             .optimize = optimize,
-            .imports = &.{
+            .imports = cli_imports,
-                .{ .name = "zfin", .module = mod },
-                .{ .name = "srf", .module = srf_mod },
-                .{ .name = "tui", .module = tui_mod },
-            },
         }),
     });
     b.installArtifact(exe);
@@ -72,15 +73,13 @@ pub fn build(b: *std.Build) void {
         run_cmd.addArgs(args);
     }
 
-    // Tests
+    // Tests: Zig test discovery doesn't cross module boundaries, so each
+    // module (lib, TUI, CLI) needs its own test target.
     const test_step = b.step("test", "Run all tests");
 
     const mod_tests = b.addTest(.{ .root_module = mod });
     test_step.dependOn(&b.addRunArtifact(mod_tests).step);
 
-    const exe_tests = b.addTest(.{ .root_module = exe.root_module });
-    test_step.dependOn(&b.addRunArtifact(exe_tests).step);
-
     const tui_tests = b.addTest(.{ .root_module = b.createModule(.{
         .root_source_file = b.path("src/tui/main.zig"),
         .target = target,
@@ -89,6 +88,14 @@ pub fn build(b: *std.Build) void {
     }) });
     test_step.dependOn(&b.addRunArtifact(tui_tests).step);
 
+    const cli_tests = b.addTest(.{ .root_module = b.createModule(.{
+        .root_source_file = b.path("src/cli/main.zig"),
+        .target = target,
+        .optimize = optimize,
+        .imports = cli_imports,
+    }) });
+    test_step.dependOn(&b.addRunArtifact(cli_tests).step);
+
     // Docs
     const lib = b.addLibrary(.{
         .name = "zfin",
@@ -108,6 +115,21 @@ pub fn build(b: *std.Build) void {
         .install_subdir = "docs",
     }).step);
 
-    // Coverage: `zig build coverage` (Linux only, uses kcov)
+    // Coverage: `zig build coverage` (uses kcov, Linux x86_64/aarch64 only)
-    _ = Coverage.addCoverageStep(b, mod, "zfin");
+    {
+        const cov = Coverage.init(b);
+        _ = cov.addModule(mod, "zfin-lib");
+        _ = cov.addModule(b.createModule(.{
+            .root_source_file = b.path("src/tui/main.zig"),
+            .target = target,
+            .optimize = optimize,
+            .imports = tui_imports,
+        }), "zfin-tui");
+        _ = cov.addModule(b.createModule(.{
+            .root_source_file = b.path("src/cli/main.zig"),
+            .target = target,
+            .optimize = optimize,
+            .imports = cli_imports,
+        }), "zfin-cli");
+    }
 }

build/Coverage.zig

@@ -4,118 +4,153 @@ const Build = std.Build;
 
 const Coverage = @This();
 
-/// Adds test coverage. This will create a new test coverage executable to the
+/// Whether the host platform supports kcov-based coverage.
-/// build graph, generated only if coverage is a target. It will create an
+/// Only x86_64 and aarch64 Linux are supported (kcov binary availability).
-/// option -Dcoverage-threshold that will fail the build if the threshold is
+/// On unsupported platforms, the coverage step will fail at runtime with
-/// not met. It will also add a step that downloads a zig fork of the kcov
+/// a clear error from the kcov download or execution step.
-/// executable into zig cache if it doesn't already exist
+// pub const supported = builtin.os.tag == .linux and
+//     (builtin.cpu.arch == .x86_64 or builtin.cpu.arch == .aarch64);
+
+/// Initialize coverage infrastructure. Creates the "coverage" build step,
+/// registers build options (-Dcoverage-threshold, -Dcoverage-dir),
+/// and sets up the kcov download step. The kcov binary is downloaded into the
+/// zig cache on first use and reused thereafter.
 ///
-/// Because it is creating a new test executable from the root module provided,
+/// Use `zig build coverage --verbose` to see per-file coverage breakdown.
+///
+/// Call `addModule()` on the returned value to add test modules to the coverage run.
+/// Each module gets its own kcov invocation, threshold check, and output subdirectory.
+///
+/// Because addModule creates a new test executable from the root module provided,
 /// if there are any linking steps being done to your test executable, those
-/// must also be done to the test_exe returned by this function
+/// must also be done to the test_exe returned by addModule.
-pub fn addCoverageStep(b: *Build, root_module: *Build.Module, coverage_name: []const u8) *Coverage {
+pub fn init(b: *Build) Coverage {
-    //verify host requirements
-    {
-        const supported = builtin.os.tag == .linux and
-            (builtin.cpu.arch == .x86_64 or builtin.cpu.arch == .aarch64);
-
-        if (!supported)
-            @panic("Coverage only supported on x86_64-linux or aarch64-linux");
-    }
-
     // Add options
     const coverage_threshold = b.option(u7, "coverage-threshold", "Minimum coverage percentage required") orelse 0;
     const coverage_dir = b.option([]const u8, "coverage-dir", "Coverage output directory") orelse
         b.pathJoin(&.{ b.build_root.path orelse ".", "coverage" });
     const coverage_step = b.step("coverage", "Generate test coverage report");
 
-    // Set up kcov download
+    // Set up kcov download.
-    // We can't do it directly because we are sandboxed during build, but
+    // We can't download directly because we are sandboxed during build, but
-    // we can create a program and run that program. First we need the destination
+    // we can create a helper program and run it. First we need the destination
-    // directory
+    // directory, keyed by architecture.
-    const kcov = blk: {
+    const arch_name = switch (builtin.cpu.arch) {
-        const arch_name = switch (builtin.cpu.arch) {
+        .x86_64 => "x86_64",
-            .x86_64 => "x86_64",
+        .aarch64 => "aarch64",
-            .aarch64 => "aarch64",
+        else => @tagName(builtin.cpu.arch),
-            else => unreachable,
-        };
-
-        const Algo = std.crypto.hash.sha2.Sha256;
-        var hasher = Algo.init(.{});
-        hasher.update("kcov-");
-        hasher.update(arch_name);
-        var cache_hash: [Algo.digest_length]u8 = undefined;
-        hasher.final(&cache_hash);
-
-        const cache_dir = b.pathJoin(&.{
-            b.cache_root.path.?,
-            "o",
-            b.fmt("{s}", .{std.fmt.bytesToHex(cache_hash, .lower)}),
-        });
-
-        const kcov_name = b.fmt("kcov-{s}", .{arch_name});
-        break :blk .{ .path = b.pathJoin(&.{ cache_dir, kcov_name }), .arch = arch_name };
     };
 
-    // Create download and coverage build steps
+    const Algo = std.crypto.hash.sha2.Sha256;
-    return blk: {
+    var hasher = Algo.init(.{});
-        const download_exe = b.addExecutable(.{
+    hasher.update("kcov-");
-            .name = "download-kcov",
+    hasher.update(arch_name);
-            .root_module = b.createModule(.{
+    var cache_hash: [Algo.digest_length]u8 = undefined;
-                .root_source_file = b.path("build/download_kcov.zig"),
+    hasher.final(&cache_hash);
-                .target = b.resolveTargetQuery(.{}),
-            }),
-        });
 
-        const run_download = b.addRunArtifact(download_exe);
+    const cache_dir = b.pathJoin(&.{
-        run_download.addArg(kcov.path);
+        b.cache_root.path.?,
-        run_download.addArg(kcov.arch);
+        "o",
+        b.fmt("{s}", .{std.fmt.bytesToHex(cache_hash, .lower)}),
+    });
 
-        const run_coverage = b.addSystemCommand(&.{kcov.path});
+    const kcov_path = b.pathJoin(&.{ cache_dir, b.fmt("kcov-{s}", .{arch_name}) });
-        const include_path = b.pathJoin(&.{ b.build_root.path.?, "src" });
-        run_coverage.addArgs(&.{ "--include-path", include_path });
-        const css_file = b.pathJoin(&.{ b.build_root.path.?, "build", "bcov.css" });
-        run_coverage.addArg(b.fmt("--configure=css-file={s}", .{css_file}));
-        run_coverage.addArg(coverage_dir);
-        const test_exe = b.addTest(.{
-            .name = coverage_name,
-            .root_module = root_module,
-            // we need to set the test exe to use llvm as the self hosted backend
-            // does not support the data kcov needs
-            .use_llvm = true,
-        });
-        run_coverage.addArtifactArg(test_exe);
-        run_coverage.step.dependOn(&test_exe.step);
-        run_coverage.step.dependOn(&run_download.step);
 
-        const json_path = b.fmt("{s}/{s}/coverage.json", .{ coverage_dir, coverage_name });
+    // Create the download helper executable
-        const verbose = b.option(bool, "coverage-verbose", "Show test coverage for each file") orelse false;
+    const download_exe = b.addExecutable(.{
-        const check_step = create(b, test_exe, json_path, coverage_threshold, verbose);
+        .name = "download-kcov",
-        check_step.step.dependOn(&run_coverage.step);
+        .root_module = b.createModule(.{
-        coverage_step.dependOn(&check_step.step);
+            .root_source_file = b.path("build/download_kcov.zig"),
-        break :blk check_step;
+            .target = b.resolveTargetQuery(.{}),
+        }),
+    });
+
+    const run_download = b.addRunArtifact(download_exe);
+    run_download.addArg(kcov_path);
+    run_download.addArg(arch_name);
+
+    return .{
+        .b = b,
+        .coverage_step = coverage_step,
+        .coverage_dir = coverage_dir,
+        .coverage_threshold = coverage_threshold,
+        .kcov_path = kcov_path,
+        .run_download = run_download,
     };
 }
 
-step: Build.Step,
+/// Add a test module to the coverage run. Each module gets its own kcov
-json_path: []const u8,
+/// invocation and threshold check, all wired into the shared "coverage" step.
-threshold: u7,
+/// Returns the test executable so the caller can add any extra linking steps.
-test_exe: *std.Build.Step.Compile,
+pub fn addModule(self: Coverage, root_module: *Build.Module, name: []const u8) *Build.Step.Compile {
-verbose: bool,
+    const b = self.b;
 
-pub fn create(owner: *Build, test_exe: *std.Build.Step.Compile, xml_path: []const u8, threshold: u7, verbose: bool) *Coverage {
+    // Set up kcov run: filter to src/ only, use custom CSS for HTML report
+    const run_coverage = b.addSystemCommand(&.{self.kcov_path});
+    const include_path = b.pathJoin(&.{ b.build_root.path.?, "src" });
+    run_coverage.addArgs(&.{ "--include-path", include_path });
+    const css_file = b.pathJoin(&.{ b.build_root.path.?, "build", "bcov.css" });
+    run_coverage.addArg(b.fmt("--configure=css-file={s}", .{css_file}));
+    run_coverage.addArg(self.coverage_dir);
+
+    // Create a test executable for this module.
+    // We need to set use_llvm because the self-hosted backend
+    // does not emit the DWARF data that kcov needs.
+    const test_exe = b.addTest(.{
+        .name = name,
+        .root_module = root_module,
+        .use_llvm = true,
+    });
+    run_coverage.addArtifactArg(test_exe);
+    run_coverage.step.dependOn(&test_exe.step);
+    run_coverage.step.dependOn(&self.run_download.step);
+
+    // Wire up the threshold check step (reads coverage.json after kcov finishes)
+    const json_path = b.fmt("{s}/{s}/coverage.json", .{ self.coverage_dir, name });
+    const check_step = create(b, test_exe, json_path, self.coverage_threshold);
+    check_step.step.dependOn(&run_coverage.step);
+    self.coverage_step.dependOn(&check_step.step);
+
+    return test_exe;
+}
+
+// ── Coverage struct fields ──────────────────────────────────
+
+// Fields used by init() to configure the shared coverage infrastructure
+b: *Build,
+coverage_step: *Build.Step,
+coverage_dir: []const u8,
+coverage_threshold: u7,
+kcov_path: []const u8,
+run_download: *Build.Step.Run,
+
+// Fields used by make() for per-module threshold checking.
+// These are only meaningful on instances created by create(), not by init().
+step: Build.Step = undefined,
+json_path: []const u8 = "",
+threshold: u7 = 0,
+test_exe: *Build.Step.Compile = undefined,
+
+/// Create a coverage check step that reads the kcov JSON output after
+/// the coverage run completes and verifies the threshold is met.
+fn create(owner: *Build, test_exe: *Build.Step.Compile, json_path: []const u8, threshold: u7) *Coverage {
     const check = owner.allocator.create(Coverage) catch @panic("OOM");
     check.* = .{
+        .b = owner,
+        .coverage_step = undefined,
+        .coverage_dir = "",
+        .coverage_threshold = 0,
+        .kcov_path = "",
+        .run_download = undefined,
         .step = Build.Step.init(.{
             .id = .custom,
             .name = "check coverage",
             .owner = owner,
             .makeFn = make,
         }),
-        .json_path = xml_path,
+        .json_path = json_path,
         .threshold = threshold,
         .test_exe = test_exe,
-        .verbose = verbose,
     };
     return check;
 }
@@ -144,6 +179,9 @@ const File = struct {
     }
 };
 
+/// Build step make function: reads the kcov coverage.json output,
+/// prints summary (and per-file breakdown if verbose), and fails
+/// the build if coverage is below the configured threshold.
 fn make(step: *Build.Step, options: Build.Step.MakeOptions) !void {
     _ = options;
     const check: *Coverage = @fieldParentPtr("step", step);
@@ -162,7 +200,7 @@ fn make(step: *Build.Step, options: Build.Step.MakeOptions) !void {
     var stdout_buffer: [1024]u8 = undefined;
     var stdout_writer = std.fs.File.stdout().writer(&stdout_buffer);
     const stdout = &stdout_writer.interface;
-    if (step.owner.verbose or check.verbose) {
+    if (step.owner.verbose) {
         const files = coverage.files;
         std.mem.sort(File, files, files, File.coverageLessThanDesc);
         for (files) |f|

src/tui/main.zig

@@ -3866,6 +3866,12 @@ fn freeWatchlist(allocator: std.mem.Allocator, watchlist: ?[][]const u8) void {
     }
 }
 
+// Force test discovery for imported TUI sub-modules
+comptime {
+    _ = keybinds;
+    _ = theme_mod;
+}
+
 /// Entry point for the interactive TUI.
 pub fn run(allocator: std.mem.Allocator, config: zfin.Config, args: []const []const u8) !void {
     var portfolio_path: ?[]const u8 = null;