feat: support non-string attrs in swift_package_tool (#1316)

Sort of missed doing this in #1307 but it provides a nicer interface for
users and will support the `dict` attr for the upcoming Swift Package
Registry support.

docs/bzlmod_extensions_overview.md

@@ -56,9 +56,9 @@ Used to configure the flags used when running the `swift package` binary.
 | :------------- | :------------- | :------------- | :------------- | :------------- |
 | <a id="swift_deps.configure_swift_package-build_path"></a>build_path |  The relative path within the runfiles tree for the Swift Package Manager build directory.   | String | optional |  `".build"`  |
 | <a id="swift_deps.configure_swift_package-cache_path"></a>cache_path |  The relative path within the runfiles tree for the shared Swift Package Manager cache directory.   | String | optional |  `".cache"`  |
-| <a id="swift_deps.configure_swift_package-dependency_caching"></a>dependency_caching |  Whether to enable the dependency cache.   | String | optional |  `"true"`  |
+| <a id="swift_deps.configure_swift_package-dependency_caching"></a>dependency_caching |  Whether to enable the dependency cache.   | Boolean | optional |  `True`  |
 | <a id="swift_deps.configure_swift_package-manifest_cache"></a>manifest_cache |  Caching mode of Package.swift manifests (shared: shared cache, local: package's build directory, none: disabled)   | String | optional |  `"shared"`  |
-| <a id="swift_deps.configure_swift_package-manifest_caching"></a>manifest_caching |  Whether to enable build manifest caching.   | String | optional |  `"true"`  |
+| <a id="swift_deps.configure_swift_package-manifest_caching"></a>manifest_caching |  Whether to enable build manifest caching.   | Boolean | optional |  `True`  |
 
 <a id="swift_deps.from_package"></a>
 

examples/interesting_deps/MODULE.bazel

@@ -58,9 +58,9 @@ swift_deps.from_package(
 swift_deps.configure_swift_package(
     build_path = "spm-build",
     cache_path = "spm-cache",
-    dependency_caching = "false",
+    dependency_caching = False,
     manifest_cache = "none",
-    manifest_caching = "false",
+    manifest_caching = False,
 )
 use_repo(
     swift_deps,

swiftpkg/internal/swift_package_tool.bzl

@@ -24,8 +24,8 @@ def _swift_package_tool_impl(ctx):
     template_dict.add("%(package_path)s", package_path)
     template_dict.add("%(build_path)s", build_path)
     template_dict.add("%(cache_path)s", cache_path)
-    template_dict.add("%(enable_build_manifest_caching)s", ctx.attr.manifest_caching)
-    template_dict.add("%(enable_dependency_cache)s", ctx.attr.dependency_caching)
+    template_dict.add("%(enable_build_manifest_caching)s", "true" if ctx.attr.manifest_caching else "false")
+    template_dict.add("%(enable_dependency_cache)s", "true" if ctx.attr.dependency_caching else "false")
     template_dict.add("%(manifest_cache)s", ctx.attr.manifest_cache)
 
     ctx.actions.expand_template(
@@ -52,10 +52,9 @@ SWIFT_PACKAGE_CONFIG_ATTRS = {
         doc = "The relative path within the runfiles tree for the shared Swift Package Manager cache directory.",
         default = ".cache",
     ),
-    "dependency_caching": attr.string(
+    "dependency_caching": attr.bool(
         doc = "Whether to enable the dependency cache.",
-        default = "true",
-        values = ["true", "false"],
+        default = True,
     ),
     "manifest_cache": attr.string(
         doc = """Caching mode of Package.swift manifests \
@@ -64,10 +63,9 @@ SWIFT_PACKAGE_CONFIG_ATTRS = {
         default = "shared",
         values = ["shared", "local", "none"],
     ),
-    "manifest_caching": attr.string(
+    "manifest_caching": attr.bool(
         doc = "Whether to enable build manifest caching.",
-        default = "true",
-        values = ["true", "false"],
+        default = True,
     ),
 }
 

swiftpkg/internal/swift_package_tool_repo.bzl

@@ -1,23 +1,34 @@
 """Defines the `swift_package_tool_repo` repository rule that creates `swift_package_tool` targets."""
 
 load("@bazel_skylib//lib:dicts.bzl", "dicts")
+load("@bazel_skylib//lib:types.bzl", "types")
 load("//swiftpkg/internal:repository_utils.bzl", "repository_utils")
 load("//swiftpkg/internal:swift_package_tool.bzl", "SWIFT_PACKAGE_CONFIG_ATTRS")
 
-def _swift_package_tool_repo_impl(repository_ctx):
-    package_path = repository_ctx.attr.package
-
-    # Construct the list of keyword arguments for the `swift_package_tool` rule.
-    # String should be "key = \"value\""
-    # NOTE: only supports string typed values as they are all quoted
+def _package_config_attrs_to_content(attrs):
+    """Returns a BUILD file compatible string representation of the keyword arguments"""
     kwargs = repository_utils.struct_to_kwargs(
-        struct = repository_ctx.attr,
+        struct = attrs,
         keys = SWIFT_PACKAGE_CONFIG_ATTRS,
     )
-    kwarg_content = ",\n".join([
-        "    {key} = \"{value}\"".format(key = k, value = v)
-        for k, v in kwargs.items()
-    ])
+
+    kwarg_lines = []
+    for k, v in kwargs.items():
+        if types.is_string(v):
+            kwarg_lines.append("    {key} = \"{value}\"".format(key = k, value = v))
+        elif types.is_bool(v):
+            kwarg_lines.append("    {key} = {value}".format(key = k, value = "True" if v else "False"))
+        elif types.is_dict(v):
+            json_str = json.encode(v)
+            kwarg_lines.append("    {key} = {value}".format(key = k, value = json_str))
+        else:
+            fail("Unsupported value type for attribute {key}: {value}".format(key = k, value = v))
+
+    return ",\n".join(kwarg_lines)
+
+def _swift_package_tool_repo_impl(repository_ctx):
+    attrs_content = _package_config_attrs_to_content(repository_ctx.attr)
+    package_path = repository_ctx.attr.package
 
     repository_ctx.file(
         "BUILD.bazel",
@@ -28,18 +39,18 @@ swift_package_tool(
     name = "update",
     cmd = "update",
     package = "{package}",
-{kwarg_content}
+{attrs_content}
 )
 
 swift_package_tool(
     name = "resolve",
     cmd = "resolve",
     package = "{package}",
-{kwarg_content}
+{attrs_content}
 )
 """.format(
             package = package_path,
-            kwarg_content = kwarg_content,
+            attrs_content = attrs_content,
         ),
     )