Merge pull request aspect-build#1 from gonzojive/apparent-loads

feat(gazelle/kotlin): Implement language.ModuleAwareLanguage.

MODULE.bazel

@@ -12,11 +12,11 @@ bazel_dep(name = "platforms", version = "0.0.10")
 go_deps = use_extension("@gazelle//:extensions.bzl", "go_deps")
 go_deps.from_file(go_mod = "//:go.mod")
 use_repo(go_deps, "com_github_bazel_contrib_rules_jvm", "com_github_bazelbuild_buildtools", "com_github_emirpasic_gods", "com_github_go_git_go_git_v5", "com_github_google_go_cmp", "com_github_rs_zerolog", "com_github_smacker_go_tree_sitter", "com_github_yargevad_filepathx", "net_starlark_go")
-go_deps.archive_override(
-    path = "github.com/bazel-contrib/rules_jvm",
-    sha256 = "855a528d5231aa6cfa2d5bd7a2343f601a468f7af9671eecb091b0c540ce034c",
-    urls = ["http://localhost:8674/by-sha256/855a528d5231aa6cfa2d5bd7a2343f601a468f7af9671eecb091b0c540ce034c.zip"],
-)
+# go_deps.archive_override(
+#     path = "github.com/bazel-contrib/rules_jvm",
+#     sha256 = "855a528d5231aa6cfa2d5bd7a2343f601a468f7af9671eecb091b0c540ce034c",
+#     urls = ["http://localhost:8674/by-sha256/855a528d5231aa6cfa2d5bd7a2343f601a468f7af9671eecb091b0c540ce034c.zip"],
+# )
 
 go_sdk = use_extension("@io_bazel_rules_go//go:extensions.bzl", "go_sdk")
 

README.md

@@ -1,3 +1,60 @@
-A Kotlin gazelle plugin, etracted from https://github.com/aspect-build/aspect-cli
+A Kotlin plugin for [bazel's gazelle
+tool](https://github.com/bazelbuild/bazel-gazelle/tree/master) for automatically
+generating BUILD.bazel files from Kotlin source code.
 
-This repository is only for debugging. It is not intended for usage.
+### Fork status
+This code was extracted from https://github.com/aspect-build/aspect-cli. I would
+like to merge it upstream depending on how the conversation goes with the
+original authors. See https://github.com/aspect-build/aspect-cli/issues/750 for
+discussion.
+
+
+# Usage
+
+
+# Dependency resolution
+
+Gazelle must resolve what Bazel labels (like `@foo//bar/baz`) a Kotlin file depends on.
+The rules followed by this plugin are as follows:
+
+1. The dependencies of a Kotlin file are determined from the explicit imports in
+   the file. Fully-qualified identifiers present elsewhere in the file are not
+   considered when determining dependencies.
+
+2. The resolution algorithm (as implemented in `gazelle/kotlin/resolver.go`)
+
+3. An identifier matches a [Maven
+   artifact](https://maven.apache.org/repositories/artifacts.html) if one of the
+   packages declared as an export of that artifact is a package prefix
+
+4. If the import to be resolved is in the library index, the import will be resolved to that library. If `-index=true`, Gazelle builds an index of library rules in the current repository before starting dependency resolution, and this is how most dependencies are resolved.
+
+   1. For Kotlin, the match is based on the importpath attribute.
+
+   2. For proto, the match is based on the srcs attribute.
+
+
+# Terminology
+
+**identifier** is used to refer to what the Kotlin spec calls an
+[identifier](https://kotlinlang.org/spec/syntax-and-grammar.html#grammar-rule-identifier).
+This is a fully-qualified or partially-qualified name. Fully-qualified
+identifiers are used in `package` and `import` statements in Kotlin files.
+
+**parent identifier**: In this document and in the code base, "parent identifier" means
+an identifier with the last dot-delimited component removed. Sometimes it may be loosely
+used to refer to all the ancestor identifiers as well (parent, parent of parent, etc.).
+
+# Directives
+
+Many [gazelle directives](https://github.com/bazelbuild/bazel-gazelle#directives) are generic
+and will apply the the behavior of the Kotlin plugin.
+
+The Kotlin plugin has additional directives for configuring behavior:
+
+## gazelle:java_maven_install_file
+
+Specifies where the `maven_install.json` file is located.
+
+This directive is defined by the [rules_jvm gazelle plugin](), and the Kotlin
+plugins hares logic with the Java plugin to parse it.

gazelle/kotlin/BUILD.bazel

@@ -1,6 +1,8 @@
 load("@gazelle//:def.bzl", "gazelle_binary")
 load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 load("//gazelle:gazelle.bzl", "gazelle_generation_test")
+load("@bazel_skylib//lib:paths.bzl", "paths")
+load("@bazel_skylib//lib:sets.bzl", "sets")
 
 # Exclude all test data
 # gazelle:exclude tests/
@@ -49,15 +51,21 @@ gazelle_binary(
 # A separate generation test for each tests/* test case
 [
     gazelle_generation_test(
-        name = "%s_test" % test_workspace.replace("/WORKSPACE", "").replace("tests/", ""),
+        name = "%s_test" % test_dir.replace("tests/", ""),
         size = "small",
-        dir = test_workspace.replace("/WORKSPACE", ""),
+        dir = test_dir,
         env = {
             "ASPECT_CLI_LOG_DEBUG": "TRACE",
         },
         gazelle_binary = "gazelle_kotlin_binary",
     )
-    for test_workspace in glob(["tests/**/WORKSPACE"])
+    for test_dir in sets.to_list(sets.make([
+        paths.dirname(p)
+        for p in glob([
+            "tests/**/WORKSPACE",
+            "tests/**/MODULE.bazel",
+        ])
+    ]))
 ]
 
 go_test(

gazelle/kotlin/language.go

@@ -1,6 +1,8 @@
 package gazelle
 
 import (
+	"fmt"
+
 	jvm_maven "github.com/bazel-contrib/rules_jvm/java/gazelle/private/maven"
 	"github.com/bazelbuild/bazel-gazelle/config"
 	"github.com/bazelbuild/bazel-gazelle/language"
@@ -11,14 +13,24 @@ import (
 const LanguageName = "kotlin"
 
 const (
-	KtJvmLibrary              = "kt_jvm_library"
-	KtJvmBinary               = "kt_jvm_binary"
-	RulesKotlinRepositoryName = "io_bazel_rules_kotlin"
+	KtJvmLibrary = "kt_jvm_library"
+	KtJvmBinary  = "kt_jvm_binary"
+	// rulesKotlinWorkspaceBasedRepositoryName is the canonical repository name of the
+	// rules_kotlin repository for WORKSPACE-based projects.
+	rulesKotlinWorkspaceBasedRepositoryName = "io_bazel_rules_kotlin"
+
+	// rulesKotlinModuleName is the name of [rules_kotlin bzlmod module].
+	//
+	// [rules_kotlin bzlmod module]: https://registry.bazel.build/modules/rules_kotlin.
+	rulesKotlinModuleName = "rules_kotlin"
 )
 
 var sourceRuleKinds = treeset.NewWithStringComparator(KtJvmLibrary)
 
-var _ language.Language = (*kotlinLang)(nil)
+var (
+	_ language.Language            = (*kotlinLang)(nil)
+	_ language.ModuleAwareLanguage = (*kotlinLang)(nil)
+)
 
 // The Gazelle extension for TypeScript rules.
 // TypeScript satisfies the language.Language interface including the
@@ -62,22 +74,45 @@ var kotlinKinds = map[string]rule.KindInfo{
 	},
 }
 
-var kotlinLoads = []rule.LoadInfo{
-	{
-		Name: "@" + RulesKotlinRepositoryName + "//kotlin:jvm.bzl",
-		Symbols: []string{
-			KtJvmLibrary,
-			KtJvmBinary,
-		},
-	},
-}
-
 func (*kotlinLang) Kinds() map[string]rule.KindInfo {
 	return kotlinKinds
 }
 
-func (*kotlinLang) Loads() []rule.LoadInfo {
-	return kotlinLoads
+func (l *kotlinLang) Loads() []rule.LoadInfo {
+	return l.ApparentLoads(func(moduleName string) string {
+		switch moduleName {
+		case rulesKotlinModuleName:
+			return rulesKotlinWorkspaceBasedRepositoryName
+		default:
+			panic(fmt.Errorf("unexpected module name %q", moduleName))
+		}
+	})
+}
+
+// ApparentLoads implements [language.ModuleAwareLanguage].
+func (kt *kotlinLang) ApparentLoads(moduleToApparentName func(string) string) []rule.LoadInfo {
+	// Note from [language.ModuleAwareLanguage]:
+	//
+	// The moduleToApparentName argument is a function that resolves a given
+	// Bazel module name to the apparent repository name configured for this
+	// module in the MODULE.bazel file, or the empty string if there is no such
+	// module or the MODULE.bazel file doesn't exist. Languages should use the
+	// non-empty value returned by this function to form the repository part of
+	// the load statements they return and fall back to using the legacy
+	// WORKSPACE name otherwise.
+	rulesKotlinRepo := moduleToApparentName(rulesKotlinModuleName)
+	if rulesKotlinRepo == "" {
+		rulesKotlinRepo = rulesKotlinWorkspaceBasedRepositoryName
+	}
+	return []rule.LoadInfo{
+		{
+			Name: "@" + rulesKotlinRepo + "//kotlin:jvm.bzl",
+			Symbols: []string{
+				KtJvmLibrary,
+				KtJvmBinary,
+			},
+		},
+	}
 }
 
 func (*kotlinLang) Fix(c *config.Config, f *rule.File) {}

gazelle/kotlin/tests/simple_file_bzlmod/BUILD.out

@@ -0,0 +1,9 @@
+load("@rules_kotlin//kotlin:jvm.bzl", "kt_jvm_library")
+
+kt_jvm_library(
+    name = "root",
+    srcs = [
+        "lib.kt",
+        "libs.kts",
+    ],
+)

gazelle/kotlin/tests/simple_file_bzlmod/MODULE.bazel

@@ -0,0 +1,21 @@
+module(
+    name = "simple",
+    version = "0.0.1",
+)
+
+bazel_dep(name = "rules_kotlin", version = "1.9.6")
+bazel_dep(name = "rules_jvm_external", version = "6.4")
+
+maven = use_extension("@rules_jvm_external//:extensions.bzl", "maven")
+
+maven.install(
+    artifacts = [
+        "com.google.truth:truth:1.1.2",
+        "junit:junit:4.13.2",
+    ],
+    lock_file = "//:maven_install.json",
+    repositories = [
+        "https://repo1.maven.org/maven2",
+    ],
+)
+use_repo(maven, "maven")

gazelle/kotlin/tests/simple_file_bzlmod/lib.kt

@@ -0,0 +1,5 @@
+// Hello World Program
+
+fun hello() {
+    println("Hello world!")
+}

gazelle/kotlin/tests/simple_file_bzlmod/libs.kts

@@ -0,0 +1,5 @@
+// Hello World Program
+
+fun hello() {
+    println("Hello world!")
+}