Add support for ktfmt

README.md

@@ -16,6 +16,7 @@ Supported languages:
 | --------- | ------------------------- | -------------------------------------------------------------- |
 | ✓         | Python                    | [Black](https://pypi.org/project/black/)                       |
 | ✓         | Java                      | [google-java-format]                                           |
+| ✓         | Kotlin                    | [ktfmt](https://github.com/facebook/ktfmt)                     |
 | ✓         | JavaScript/TypeScript/TSX | [Prettier]                                                     |
 | ✓         | CSS/HTML                  | [Prettier]                                                     |
 | ✓         | JSON                      | [Prettier]                                                     |
@@ -107,6 +108,7 @@ Add some of these lines to `.bazelrc`:
 run --@aspect_rules_format//format:go_enabled
 run --@aspect_rules_format//format:java_enabled
 run --@aspect_rules_format//format:jsonnet_enabled
+run --@aspect_rules_format//format:kotlin_enabled
 run --@aspect_rules_format//format:proto_enabled
 run --@aspect_rules_format//format:python_enabled
 run --@aspect_rules_format//format:swift_enabled

examples/hello.kt

@@ -0,0 +1,3 @@
+fun main() {
+  println("Hello, world!")
+}

format/BUILD.bazel

@@ -34,6 +34,12 @@ java_binary(
     runtime_deps = ["@google-java-format//jar"],
 )
 
+java_binary(
+    name = "ktfmt",
+    main_class = "com.facebook.ktfmt.cli.Main",
+    runtime_deps = ["@ktfmt//jar"],
+)
+
 alias(
     name = "black",
     # Don't use the requirements.bzl#entry_point helper as that makes an eager load
@@ -116,6 +122,11 @@ sh_binary(
             ":format_java": [":java-format"],
             "//conditions:default": [],
         },
+    ) + select(
+        {
+            ":format_kotlin": [":ktfmt"],
+            "//conditions:default": [],
+        },
     ) + select(
         {
             ":format_swift": [":swiftformat"],

format/format.sh

@@ -57,6 +57,7 @@ case "$mode" in
    prettiermode="--check"
    blackmode="--check"
    javamode="--set-exit-if-changed --dry-run"
+   ktmode="--set-exit-if-changed --dry-run"
    gofmtmode="-l"
    bufmode="format -d --exit-code"
    tfmode="-check -diff"
@@ -67,6 +68,7 @@ case "$mode" in
    prettiermode="--write"
    blackmode=""
    javamode="--replace"
+   ktmode=""
    gofmtmode="-w"
    bufmode="format -w"
    tfmode=""
@@ -162,6 +164,17 @@ if [ -n "$files" ] && [ -n "$bin" ]; then
   echo "$files" | tr \\n \\0 | JAVA_RUNFILES="${RUNFILES_MANIFEST_FILE%_manifest}" xargs -0 $bin $javamode
 fi
 
+if [ "$#" -eq 0 ]; then
+  files=$(git ls-files '*.kt')
+else
+  files=$(find "$@" -name '*.kt')
+fi
+bin=$(rlocation aspect_rules_format/format/ktfmt)
+if [ -n "$files" ] && [ -n "$bin" ]; then
+  echo "Running ktfmt..."
+  echo "$files" | tr \\n \\0 | xargs -0 $bin $ktmode
+fi
+
 if [ "$#" -eq 0 ]; then
   files=$(git ls-files '*.go')
 else

format/langs.bzl

@@ -3,4 +3,4 @@
 # These are the ones users can enable.
 # We always do Prettier since it does so many languages.
 # keep sorted
-LANGS = ["go", "java", "jsonnet", "proto", "python", "swift", "terraform"]
+LANGS = ["go", "java", "jsonnet", "kotlin", "proto", "python", "swift", "terraform"]

format/repositories.bzl

@@ -96,6 +96,11 @@ def rules_format_dependencies():
         url = "https://github.com/google/google-java-format/releases/download/v1.17.0/google-java-format-1.17.0-all-deps.jar",
     )
 
+    http_jar(
+        name = "ktfmt",
+        url = "https://repo1.maven.org/maven2/com/facebook/ktfmt/0.46/ktfmt-0.46-jar-with-dependencies.jar",
+    )
+
     http_archive(
         name = "io_bazel_rules_go",
         sha256 = "099a9fb96a376ccbbb7d291ed4ecbdfd42f6bc822ab77ae6f1b5cb9e914e94fa",