[J2KT] Add Source.emptyIf() and use it in places where double negat…

…ion occurs. PiperOrigin-RevId: 707089461
google · Dec 17, 2024 · eedb63d · eedb63d
1 parent 4f5b984
commit eedb63d
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Showing 6 changed files with 27 additions and 14 deletions.
diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/ExpressionRenderer.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/ExpressionRenderer.kt
@@ -508,7 +508,7 @@ internal data class ExpressionRenderer(
       dotSeparated(
         qualifierSource(expression),
         spaceSeparated(
-          Source.emptyUnless(expression.anonymousInnerClass != null) {
+          Source.emptyIf(expression.anonymousInnerClass == null) {
             spaceSeparated(OBJECT_KEYWORD, COLON)
           },
           join(

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/JsInteropAnnotationRenderer.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/JsInteropAnnotationRenderer.kt
@@ -29,6 +29,7 @@ import com.google.j2cl.transpiler.backend.kotlin.KotlinSource.assignment
 import com.google.j2cl.transpiler.backend.kotlin.KotlinSource.literal
 import com.google.j2cl.transpiler.backend.kotlin.source.Source
 import com.google.j2cl.transpiler.backend.kotlin.source.Source.Companion.dotSeparated
+import com.google.j2cl.transpiler.backend.kotlin.source.Source.Companion.emptyIf
 import com.google.j2cl.transpiler.backend.kotlin.source.Source.Companion.emptyUnless
 import com.google.j2cl.transpiler.backend.kotlin.source.Source.Companion.newLineSeparated
 import com.google.j2cl.transpiler.backend.kotlin.source.Source.Companion.source
@@ -189,7 +190,7 @@ internal data class JsInteropAnnotationRenderer(val nameRenderer: NameRenderer)
 
   companion object {
     private fun nameParameterSource(typeDeclaration: TypeDeclaration): Source =
-      emptyUnless(typeDeclaration.simpleJsName != typeDeclaration.simpleSourceName) {
+      emptyIf(typeDeclaration.simpleJsName == typeDeclaration.simpleSourceName) {
         nameParameterSource(typeDeclaration.simpleJsName)
       }
 
@@ -203,7 +204,7 @@ internal data class JsInteropAnnotationRenderer(val nameRenderer: NameRenderer)
       name: String,
       value: Boolean,
       defaultValue: Boolean,
-    ): Source = emptyUnless(value != defaultValue) { assignment(source(name), literal(value)) }
+    ): Source = emptyIf(value == defaultValue) { assignment(source(name), literal(value)) }
 
     private val MethodDescriptor.hasJsConstructorAnnotation
       get() = originalJsInfo.hasJsMemberAnnotation && isJsConstructor

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/MemberRenderer.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/MemberRenderer.kt
@@ -122,9 +122,9 @@ internal data class MemberRenderer(val nameRenderer: NameRenderer, val enclosing
       Source.emptyUnless(!isKtPrimaryConstructor(method) || statements.isNotEmpty()) {
         spaceSeparated(
           methodHeaderSource(method),
-          Source.emptyUnless(!method.isAbstract && !method.isNative) {
+          Source.emptyIf(method.isAbstract || method.isNative) {
             // Constructors with no statements can be rendered without curly braces.
-            Source.emptyUnless(!method.isConstructor || statements.isNotEmpty()) {
+            Source.emptyIf(method.isConstructor && statements.isEmpty()) {
               spaceSeparated(
                   Source.emptyUnless(method.descriptor.isKtProperty) {
                     join(GET_KEYWORD, inParentheses(Source.EMPTY))
@@ -219,7 +219,7 @@ internal data class MemberRenderer(val nameRenderer: NameRenderer, val enclosing
   private fun methodModifiersSource(method: Method): Source =
     spaceSeparated(
       memberDescriptorRenderer.visibilityModifierSource(method.descriptor),
-      Source.emptyUnless(!method.descriptor.enclosingTypeDescriptor.typeDeclaration.isInterface) {
+      Source.emptyIf(method.descriptor.enclosingTypeDescriptor.typeDeclaration.isInterface) {
         spaceSeparated(
           Source.emptyUnless(method.descriptor.isNative) { KotlinSource.EXTERNAL_KEYWORD },
           method.inheritanceModifierSource,
@@ -241,8 +241,8 @@ internal data class MemberRenderer(val nameRenderer: NameRenderer, val enclosing
     val parameterDescriptors = methodDescriptor.parameterDescriptors
     val parameters = method.parameters
     val renderWithNewLines = objCParameterNames != null && parameters.isNotEmpty()
-    val optionalNewLineSource = Source.emptyUnless(renderWithNewLines) { Source.NEW_LINE }
-    return Source.emptyUnless(!methodDescriptor.isKtProperty) {
+    val optionalNewLineSource = Source.emptyUnless(renderWithNewLines) { NEW_LINE }
+    return Source.emptyIf(methodDescriptor.isKtProperty) {
       inParentheses(
         join(
           indentedIf(

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/TypeDescriptorRenderer.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/TypeDescriptorRenderer.kt
@@ -116,7 +116,7 @@ internal data class TypeDescriptorRenderer(
     join(
       nameRenderer.qualifiedNameSource(arrayTypeDescriptor),
       arrayTypeDescriptor.componentTypeDescriptor.let {
-        Source.emptyUnless(!it.isPrimitive) { inAngleBrackets(child.source(it)) }
+        Source.emptyIf(it.isPrimitive) { inAngleBrackets(child.source(it)) }
       },
       nullableSuffixSource(arrayTypeDescriptor),
     )

diff --git a/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/source/Source.kt b/transpiler/java/com/google/j2cl/transpiler/backend/kotlin/source/Source.kt
@@ -42,7 +42,7 @@ private constructor(
    * source.
    */
   operator fun plus(source: Source) =
-    emptyUnless(isNotEmpty() || source.isNotEmpty()) {
+    emptyIf(isEmpty() && source.isEmpty()) {
       Source { sourceBuilder ->
         sourceBuilder.append(this)
         sourceBuilder.append(source)
@@ -95,7 +95,13 @@ private constructor(
 
     /** Returns a source containing the given string. */
     fun source(string: String) =
-      emptyUnless(string.isNotEmpty()) { Source { sourceBuilder -> sourceBuilder.append(string) } }
+      emptyIf(string.isEmpty()) { Source { sourceBuilder -> sourceBuilder.append(string) } }
+
+    /**
+     * Returns empty source if the condition is satisfied, otherwise source returned from the given
+     * function.
+     */
+    inline fun emptyIf(condition: Boolean, fn: () -> Source) = if (condition) EMPTY else fn()
 
     /**
      * Returns source returned from the given function if the condition is satisfied, otherwise
@@ -105,7 +111,7 @@ private constructor(
 
     /** Join given sources using given separator, skipping empty ones. */
     fun join(sources: Iterable<Source>, separator: String = "") =
-      emptyUnless(sources.any(Source::isNotEmpty)) {
+      emptyIf(sources.all(Source::isEmpty)) {
         Source { sourceBuilder ->
           var first = true
           for (source in sources) {
@@ -146,7 +152,7 @@ private constructor(
       spaceSeparated(LEFT_CURLY_BRACKET, source, RIGHT_CURLY_BRACKET)
 
     fun indented(source: Source) =
-      emptyUnless(source.isNotEmpty()) {
+      emptyIf(source.isEmpty()) {
         Source { sourceBuilder ->
           sourceBuilder.indent()
           sourceBuilder.append(source)

diff --git a/transpiler/javatests/com/google/j2cl/transpiler/backend/kotlin/source/SourceTest.kt b/transpiler/javatests/com/google/j2cl/transpiler/backend/kotlin/source/SourceTest.kt
@@ -160,7 +160,13 @@ class SourceTest {
   }
 
   @Test
-  fun sourceIf() {
+  fun sourceEmptyIf() {
+    Source.emptyIf(true) { sourceA }.assertBuilds("")
+    Source.emptyIf(false) { sourceA }.assertBuilds("a")
+  }
+
+  @Test
+  fun sourceEmptyUnless() {
     Source.emptyUnless(true) { sourceA }.assertBuilds("a")
     Source.emptyUnless(false) { sourceA }.assertBuilds("")
   }