Support disabling import optimization from command line

Summary:
Turns out we did not connecting this to our CLI interface, making it impossible to skip imports.

Slightly awkward naming (i.e. the flag negates), but it gets the job done, and we don't have a real parser for flags no is the dependency on one worth it.

Reviewed By: hick209

Differential Revision: D42105735

fbshipit-source-id: 8ddab2af5310fd59d86e29d6c827b33d47ab10b1

3 files changed, 37 insertions, 2 deletions

diff --git a/core/src/main/java/com/facebook/ktfmt/cli/Main.kt b/core/src/main/java/com/facebook/ktfmt/cli/Main.kt
index 0a08944..980897d 100644
--- a/core/src/main/java/com/facebook/ktfmt/cli/Main.kt
+++ b/core/src/main/java/com/facebook/ktfmt/cli/Main.kt
@@ -70,7 +70,7 @@ class Main(
   fun run(): Int {
     if (parsedArgs.fileNames.isEmpty()) {
       err.println(
-          "Usage: ktfmt [--dropbox-style | --google-style | --kotlinlang-style] [--dry-run] [--set-exit-if-changed] [--stdin-name=<name>] File1.kt File2.kt ...")
+          "Usage: ktfmt [--dropbox-style | --google-style | --kotlinlang-style] [--dry-run] [--set-exit-if-changed] [--stdin-name=<name>] [--do-not-remove-unused-imports] File1.kt File2.kt ...")
       err.println("Or: ktfmt @file")
       return 1
     }
diff --git a/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt b/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt
index 4c66efd..2c84972 100644
--- a/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt
+++ b/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt
@@ -52,6 +52,7 @@ data class ParsedArgs(
       var formattingOptions = FormattingOptions()
       var dryRun = false
       var setExitIfChanged = false
+      var removeUnusedImports = true
       var stdinName: String? = null
 
       for (arg in args) {
@@ -61,6 +62,7 @@ data class ParsedArgs(
           arg == "--kotlinlang-style" -> formattingOptions = Formatter.KOTLINLANG_FORMAT
           arg == "--dry-run" || arg == "-n" -> dryRun = true
           arg == "--set-exit-if-changed" -> setExitIfChanged = true
+          arg == "--do-not-remove-unused-imports" -> removeUnusedImports = false
           arg.startsWith("--stdin-name") -> stdinName = parseKeyValueArg(err, "--stdin-name", arg)
           arg.startsWith("--") -> err.println("Unexpected option: $arg")
           arg.startsWith("@") -> err.println("Unexpected option: $arg")
@@ -68,7 +70,13 @@ data class ParsedArgs(
         }
       }
 
-      return ParsedArgs(fileNames, formattingOptions, dryRun, setExitIfChanged, stdinName)
+      return ParsedArgs(
+          fileNames,
+          formattingOptions.copy(removeUnusedImports = removeUnusedImports),
+          dryRun,
+          setExitIfChanged,
+          stdinName,
+      )
     }
 
     private fun parseKeyValueArg(err: PrintStream, key: String, arg: String): String? {
diff --git a/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt b/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt
index 37cbf57..9f0919b 100644
--- a/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt
+++ b/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt
@@ -108,6 +108,33 @@ class ParsedArgsTest {
   }
 
   @Test
+  fun `parseOptions defaults to removing imports`() {
+    val (parsed, _) = parseTestOptions("foo.kt")
+    assertThat(parsed.formattingOptions.removeUnusedImports).isTrue()
+  }
+
+  @Test
+  fun `parseOptions recognizes --do-not-remove-unused-imports to removing imports`() {
+    val (parsed, _) = parseTestOptions("--do-not-remove-unused-imports", "foo.kt")
+    assertThat(parsed.formattingOptions.removeUnusedImports).isFalse()
+  }
+
+  @Test
+  fun `parseOptions handles dropbox style and --do-not-remove-unused-imports`() {
+    val (parsed, _) =
+        parseTestOptions("--do-not-remove-unused-imports", "--dropbox-style", "foo.kt")
+    assertThat(parsed.formattingOptions.removeUnusedImports).isFalse()
+    assertThat(parsed.formattingOptions.style).isEqualTo(FormattingOptions.Style.DROPBOX)
+  }
+
+  @Test
+  fun `parseOptions handles google style and --do-not-remove-unused-imports`() {
+    val (parsed, _) = parseTestOptions("--do-not-remove-unused-imports", "--google-style", "foo.kt")
+    assertThat(parsed.formattingOptions.removeUnusedImports).isFalse()
+    assertThat(parsed.formattingOptions.style).isEqualTo(FormattingOptions.Style.GOOGLE)
+  }
+
+  @Test
   fun `parseOptions --stdin-name`() {
     val (parsed, _) = parseTestOptions("--stdin-name=my/foo.kt")
     assertThat(parsed.stdinName).isEqualTo("my/foo.kt")