Kotlin: Add support for Kotlin type aliases

igfoo · igfoo · commit 87b433142c1e · 2022-05-10T19:51:01.000+01:00
diff --git a/java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt b/java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt
@@ -769,6 +769,18 @@ class X {
         return id
     }
 
+    private fun getTypeAliasLabel(ta: IrTypeAlias) : String {
+        val parentId = useDeclarationParent(ta.parent)
+        val label = "@\"type_alias;{$parentId};${ta.name.asString()}\""
+        return label
+    }
+
+    fun useTypeAlias(ta: IrTypeAlias): Label<out DbKt_type_alias> {
+        var label = getTypeAliasLabel(ta)
+        val id: Label<DbKt_type_alias> = tw.getLabelFor(label)
+        return id
+    }
+
     fun useVariable(v: IrVariable): Label<out DbLocalvar> {
         return tw.getVariableLabelFor<DbLocalvar>(v)
     }
@@ -793,6 +805,7 @@ open class KotlinFileExtractor(
             }
             is IrProperty -> extractProperty(declaration, parentId)
             is IrEnumEntry -> extractEnumEntry(declaration, parentId)
+            is IrTypeAlias -> extractTypeAlias(declaration) // TODO: Pass in and use parentId
             else -> logger.warnElement(Severity.ErrorSevere, "Unrecognised IrDeclaration: " + declaration.javaClass, declaration)
         }
     }
@@ -1031,6 +1044,19 @@ open class KotlinFileExtractor(
         }
     }
 
+    fun extractTypeAlias(ta: IrTypeAlias) {
+        if (ta.typeParameters.isNotEmpty()) {
+            // TODO: Extract this information
+            logger.warn(Severity.ErrorSevere, "Type alias type parameters ignored for " + ta.render())
+        }
+        val id = useTypeAlias(ta)
+        val locId = tw.getLocation(ta)
+        // TODO: We don't really want to generate any Java types here; we only want the KT type:
+        val type = useType(ta.expandedType)
+        tw.writeKt_type_alias(id, ta.name.asString(), type.kotlinResult.id)
+        tw.writeHasLocation(id, locId)
+    }
+
     fun extractBody(b: IrBody, callable: Label<out DbCallable>) {
         when(b) {
             is IrBlockBody -> extractBlockBody(b, callable, callable, 0)
diff --git a/java/ql/lib/config/semmlecode.dbscheme b/java/ql/lib/config/semmlecode.dbscheme
@@ -324,6 +324,12 @@ kt_notnull_types(
   int classid: @classorinterface ref
 )
 
+kt_type_alias(
+  unique int id: @kt_type_alias,
+  string name: string ref,
+  int kttypeid: @kt_type ref
+)
+
 @kt_type = @kt_nullable_type | @kt_notnull_type
 
 isRecord(
@@ -928,19 +934,22 @@ javadocText(
 @classorarray = @class | @array;
 @type = @primitive | @reftype;
 @callable = @method | @constructor;
+
+/** A program element that has a name. */
 @element = @file | @package | @primitive | @class | @interface | @method | @constructor | @modifier | @param | @exception | @field |
-           @annotation | @boundedtype | @array | @localvar | @expr | @stmt | @import | @fielddecl | @kt_type;
+           @annotation | @boundedtype | @array | @localvar | @expr | @stmt | @import | @fielddecl | @kt_type | @kt_type_alias;
 
 @modifiable = @member_modifiable| @param | @localvar ;
 
 @member_modifiable = @class | @interface | @method | @constructor | @field ;
 
 @member = @method | @constructor | @field | @reftype ;
 
+/** A program element that has a location. */
 @locatable = @file | @class | @interface | @fielddecl | @field | @constructor | @method | @param | @exception
              | @boundedtype | @typebound | @array | @primitive
              | @import | @stmt | @expr | @whenbranch | @localvar | @javadoc | @javadocTag | @javadocText
-             | @xmllocatable | @ktcomment;
+             | @xmllocatable | @ktcomment | @kt_type_alias;
 
 @top = @element | @locatable | @folder;
 
diff --git a/java/ql/lib/semmle/code/Location.qll b/java/ql/lib/semmle/code/Location.qll
@@ -43,6 +43,8 @@ predicate hasName(Element e, string name) {
   arrays(e, name, _, _, _, _, _)
   or
   modifiers(e, name)
+  or
+  kt_type_alias(e, name, _)
 }
 
 /**
diff --git a/java/ql/lib/semmle/code/java/KotlinType.qll b/java/ql/lib/semmle/code/java/KotlinType.qll
@@ -25,3 +25,10 @@ class KotlinNotnullType extends KotlinType, @kt_notnull_type {
   override string getAPrimaryQlClass() { result = "KotlinNotnullType" }
 }
 
+class KotlinTypeAlias extends Element, @kt_type_alias {
+  override string getAPrimaryQlClass() { result = "KotlinTypeAlias" }
+
+  KotlinType getKotlinType() {
+    kt_type_alias(this, _, result)
+  }
+}

Original file line number	Diff line number	Diff line change
`@@ -43,6 +43,8 @@ predicate hasName(Element e, string name) {`
`43`	`43`	`arrays(e, name, _, _, _, _, _)`
`44`	`44`	`or`
`45`	`45`	`modifiers(e, name)`
	`46`	`+ or`
	`47`	`+ kt_type_alias(e, name, _)`
`46`	`48`	`}`
`47`	`49`
`48`	`50`	`/**`