Add package_json parameter to ts_config and expose rule to exclude it

examples/package_json_usage/colocated/BUILD.bazel

@@ -10,7 +10,7 @@ load("@bazel_skylib//rules:build_test.bzl", "build_test")
 ts_config(
     name = "tsconfig",
     src = "tsconfig.json",
-    deps = ["package.json"],
+    package_json = "package.json",
 )
 
 ts_project(

examples/package_json_usage/imports_field/BUILD.bazel

@@ -9,7 +9,7 @@ load("@bazel_skylib//rules:build_test.bzl", "build_test")
 ts_config(
     name = "tsconfig",
     src = "//package_json_usage:tsconfig",
-    deps = ["package.json"],
+    package_json = "package.json",
 )
 
 ts_project(

examples/package_json_usage/parent_src/BUILD.bazel

@@ -6,7 +6,7 @@ load("@bazel_skylib//rules:build_test.bzl", "build_test")
 ts_config(
     name = "tsconfig",
     src = "//package_json_usage:tsconfig",
-    deps = ["package.json"],
+    package_json = "package.json",
 )
 
 ts_project(

examples/package_json_usage/self_reference/BUILD.bazel

@@ -9,7 +9,7 @@ load("@bazel_skylib//rules:build_test.bzl", "build_test")
 ts_config(
     name = "tsconfig",
     src = "//package_json_usage:tsconfig",
-    deps = ["package.json"],
+    package_json = "package.json",
 )
 
 ts_project(

ts/defs.bzl

@@ -8,11 +8,12 @@ load("@aspect_bazel_lib//lib:utils.bzl", "to_label")
 load("@aspect_tools_telemetry_report//:defs.bzl", "TELEMETRY")  # buildifier: disable=load
 load("@bazel_skylib//lib:partial.bzl", "partial")
 load("//ts/private:build_test.bzl", "build_test")
-load("//ts/private:ts_config.bzl", "write_tsconfig", _TsConfigInfo = "TsConfigInfo", _ts_config = "ts_config")
+load("//ts/private:ts_config.bzl", "write_tsconfig", _TsConfigInfo = "TsConfigInfo", _ts_config = "ts_config", _ts_config_rule = "ts_config_rule")
 load("//ts/private:ts_lib.bzl", _lib = "lib")
 load("//ts/private:ts_project.bzl", _ts_project = "ts_project")
 
 ts_config = _ts_config
+ts_config_rule = _ts_config_rule
 TsConfigInfo = _TsConfigInfo
 ts_project_rule = _ts_project
 

ts/private/ts_config.bzl

@@ -90,7 +90,7 @@ def _ts_config_impl(ctx):
         TsConfigInfo(deps = depset(files, transitive = transitive_deps)),
     ]
 
-ts_config = rule(
+ts_config_rule = rule(
     implementation = _ts_config_impl,
     attrs = {
         "deps": attr.label_list(
@@ -113,6 +113,45 @@ extended configuration file as well, to pass them both to the TypeScript compile
     toolchains = COPY_FILE_TO_BIN_TOOLCHAINS,
 )
 
+def ts_config(name, src, deps = [], package_json = None, **kwargs):
+    """Wrapper around ts_config_rule that optionally includes a package.json.
+
+    When package_json is set, an additional `name + "_without_package_json"` target
+    is created so that extending ts_configs can inherit the tsconfig without
+    receiving the package.json.
+
+    Args:
+        name: name of the resulting write_file rule
+        config: tsconfig dictionary
+        files: list of input .ts files to put in the files[] array
+        out: the file to write
+        extends: a label for a tsconfig.json file to extend from, if any
+        allow_js: value of the allowJs tsconfig property
+        resolve_json_module: value of the resolveJsonModule tsconfig property
+        package_json: a package.json file to include in deps
+        **kwargs: Other common named parameters such as `tags` or `visibility`
+    """
+    if package_json:
+        ts_config_rule(
+            name = name,
+            src = src,
+            deps = deps + [package_json],
+            **kwargs
+        )
+        ts_config_rule(
+            name = name + "_without_package_json",
+            src = src,
+            deps = deps,
+            **kwargs
+        )
+    else:
+        ts_config_rule(
+            name = name,
+            src = src,
+            deps = deps,
+            **kwargs
+        )
+
 def _write_tsconfig_rule(ctx):
     # TODO: is it useful to expand Make variables in the content?
     content = ctx.attr.content

ts/test/ts_config_test.bzl

@@ -75,7 +75,7 @@ def ts_config_test_suite(name):
     ts_config(
         name = "tsconfig_with_package_json_dep",
         src = "src_tsconfig_pkgjson.json",
-        deps = [":src_package_json"],
+        package_json = ":src_package_json",
     )
     ts_project(
         name = "use_tsconfig_with_package_json_dep",
@@ -85,6 +85,27 @@ def ts_config_test_suite(name):
         tsconfig = ":tsconfig_with_package_json_dep",
     )
 
+    # The _without_package_json companion target created by ts_config's
+    # package_json parameter — should NOT propagate the package.json.
+    write_file(
+        name = "src_tsconfig_nopkg",
+        out = "src_tsconfig_nopkg.json",
+        content = ["""{"compilerOptions": {"declaration": true, "outDir": "nopkg-outdir"}}"""],
+        tags = ["manual"],
+    )
+    ts_config(
+        name = "tsconfig_nopkg",
+        src = "src_tsconfig_nopkg.json",
+        package_json = ":src_package_json",
+    )
+    ts_project(
+        name = "use_tsconfig_without_package_json",
+        srcs = [":src_ts"],
+        declaration = True,
+        out_dir = "nopkg-outdir",
+        tsconfig = ":tsconfig_nopkg_without_package_json",
+    )
+
     # ts_config whose src is another ts_config target (mirrors the
     # examples/package_json_usage/parent_src pattern, where a child
     # ts_config consumes a parent ts_config's bin-tree-copied tsconfig.json
@@ -102,7 +123,7 @@ def ts_config_test_suite(name):
     ts_config(
         name = "tsconfig_wrapping_ts_config",
         src = ":tsconfig_wrap_parent",
-        deps = [":src_package_json"],
+        package_json = ":src_package_json",
     )
     ts_project(
         name = "use_tsconfig_wrapping_ts_config",
@@ -185,6 +206,11 @@ def ts_config_test_suite(name):
         target_under_test = "use_tsconfig_wrapping_ts_config",
     )
 
+    _ts_project_does_not_see_package_json_test(
+        name = "tsconfig_without_package_json_test",
+        target_under_test = "use_tsconfig_without_package_json",
+    )
+
     native.test_suite(
         name = name,
         tests = [
@@ -195,6 +221,7 @@ def ts_config_test_suite(name):
             ":outputs_use_dict_extending_tsconfig_target_test",
             ":tsconfig_with_package_json_dep_test",
             ":tsconfig_wrapping_ts_config_test",
+            ":tsconfig_without_package_json_test",
         ],
     )
 
@@ -257,3 +284,22 @@ def _ts_project_sees_package_json_in_tsc_inputs_test_impl(ctx):
     return analysistest.end(env)
 
 _ts_project_sees_package_json_in_tsc_inputs_test = analysistest.make(_ts_project_sees_package_json_in_tsc_inputs_test_impl)
+
+def _ts_project_does_not_see_package_json_test_impl(ctx):
+    """Asserts that the _without_package_json companion target does not
+    propagate a package.json to the tsc action inputs."""
+    env = analysistest.begin(ctx)
+    target_under_test = analysistest.target_under_test(env)
+
+    action_input_paths = [f.path for f in target_under_test[OutputGroupInfo]._action_inputs.to_list()]
+    package_json_inputs = [p for p in action_input_paths if p.endswith("/package.json")]
+    asserts.equals(
+        env,
+        0,
+        len(package_json_inputs),
+        "expected no package.json in tsc action inputs for the _without_package_json target, got: {}".format(package_json_inputs),
+    )
+
+    return analysistest.end(env)
+
+_ts_project_does_not_see_package_json_test = analysistest.make(_ts_project_does_not_see_package_json_test_impl)