Merge pull request github#25 from github/kotlin-getclass

Extract ::class expressions

Author: tamasvajk

java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt

@@ -308,17 +308,20 @@ class KotlinFileExtractor(val logger: FileLogger, val tw: FileTrapWriter, val fi
     }
 
     fun useClass(c: IrClass): Label<out DbClassorinterface> {
-        if(c.name.asString() == "Any" || c.name.asString() == "Unit") {
+        // todo: fix this
+        if (c.origin == IrDeclarationOrigin.IR_EXTERNAL_DECLARATION_STUB ||
+            c.origin == IrDeclarationOrigin.IR_EXTERNAL_JAVA_DECLARATION_STUB) {
             if(tw.getExistingLabelFor<DbClass>(getClassLabel(c)) == null) {
-                return extractClass(c)
+                return extractExternalClass(c)
             }
         }
         return addClassLabel(c)
     }
 
-    fun extractClass(c: IrClass): Label<out DbClassorinterface> {
+    fun extractExternalClass(c: IrClass): Label<out DbClassorinterface> {
+        // todo: fix this.
+        // temporarily only extract the class or interface without any members.
         val id = addClassLabel(c)
-        val locId = tw.getLocation(c)
         val pkg = c.packageFqName?.asString() ?: ""
         val cls = c.name.asString()
         val pkgId = extractPackage(pkg)
@@ -331,6 +334,12 @@ class KotlinFileExtractor(val logger: FileLogger, val tw: FileTrapWriter, val fi
             val classId = id as Label<out DbClass>
             tw.writeClasses(classId, cls, pkgId, classId)
         }
+        return id
+    }
+
+    fun extractClass(c: IrClass): Label<out DbClassorinterface> {
+        val id = extractExternalClass(c)
+        val locId = tw.getLocation(c)
         tw.writeHasLocation(id, locId)
         for(t in c.superTypes) {
             when(t) {
@@ -761,7 +770,16 @@ class KotlinFileExtractor(val logger: FileLogger, val tw: FileTrapWriter, val fi
                         tw.writeWhen_branch_else(bId)
                     }
                 }
-            } else -> {
+            }
+            is IrGetClass -> {
+                val id = tw.getFreshIdLabel<DbGetclassexpr>()
+                val locId = tw.getLocation(e)
+                val typeId = useType(e.type)
+                tw.writeExprs_getclassexpr(id, typeId, parent, idx)
+                tw.writeHasLocation(id, locId)
+                extractExpression(e.argument, callable, id, 0)
+            }
+            else -> {
                 logger.warnElement(Severity.ErrorSevere, "Unrecognised IrExpression: " + e.javaClass, e)
             }
         }

java/ql/lib/config/semmlecode.dbscheme

@@ -652,6 +652,7 @@ case @expr.kind of
 | 72  = @intersectiontypeaccess
 | 73  = @switchexpr
 | 74  = @whenexpr
+| 75  = @getclassexpr
 ;
 
 /** Holds if this `when` expression was written as an `if` expression. */

java/ql/lib/semmle/code/java/Expr.qll

@@ -2043,9 +2043,7 @@ class WhenExpr extends Expr, @whenexpr {
   override string getAPrimaryQlClass() { result = "WhenExpr" }
 
   /** Gets the `i`th branch. */
-  WhenBranch getBranch(int i) {
-    when_branch(result, this, i)
-  }
+  WhenBranch getBranch(int i) { when_branch(result, this, i) }
 }
 
 /** A Kotlin `when` branch. */
@@ -2063,3 +2061,13 @@ class WhenBranch extends Top, @whenbranch {
 
   override string getAPrimaryQlClass() { result = "WhenBranch" }
 }
+
+/** A Kotlin `::class` expression. */
+class ClassExpr extends Expr, @getclassexpr {
+  /** Gets the expression whose class is being returned. */
+  Expr getExpr() { result.isNthChildOf(this, 0) }
+
+  override string toString() { result = "::class" }
+
+  override string getAPrimaryQlClass() { result = "ClassExpr" }
+}

java/ql/test/kotlin/library-tests/classes/superTypes.expected

@@ -6,4 +6,3 @@
 | classes.kt:28:1:29:1 | ClassSix | classes.kt:12:1:15:1 | ClassFour |
 | classes.kt:28:1:29:1 | ClassSix | classes.kt:20:1:22:1 | IF1 |
 | classes.kt:28:1:29:1 | ClassSix | classes.kt:24:1:26:1 | IF2 |
-| file://:0:0:0:0 | Unit | file://:0:0:0:0 | Any |

java/ql/test/kotlin/library-tests/exprs/exprs.expected

@@ -41,12 +41,15 @@
 | exprs.kt:46:12:46:14 | 123 | IntegerLiteral |
 | exprs.kt:46:12:46:20 | ... + ... | AddExpr |
 | exprs.kt:46:18:46:20 | 456 | IntegerLiteral |
+| exprs.kt:50:13:50:16 | true | BooleanLiteral |
+| exprs.kt:50:13:50:23 | ::class | ClassExpr |
 | file://:0:0:0:0 | b1 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | b2 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | b6 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | b7 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | b8 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | c | LocalVariableDeclExpr |
+| file://:0:0:0:0 | d | LocalVariableDeclExpr |
 | file://:0:0:0:0 | i1 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | i2 | LocalVariableDeclExpr |
 | file://:0:0:0:0 | i3 | LocalVariableDeclExpr |

java/ql/test/kotlin/library-tests/exprs/exprs.kt

@@ -46,3 +46,6 @@ TODO
     return 123 + 456
 }
 
+fun getClass() {
+    val d = true::class
+}

java/ql/test/kotlin/library-tests/methods/methods.expected

@@ -1,10 +1,3 @@
-| file://:0:0:0:0 | <init> |
-| file://:0:0:0:0 | equals |
-| file://:0:0:0:0 | equals |
-| file://:0:0:0:0 | hashCode |
-| file://:0:0:0:0 | hashCode |
-| file://:0:0:0:0 | toString |
-| file://:0:0:0:0 | toString |
 | methods2.kt:4:1:5:1 | fooBarTopLevelMethod |
 | methods2.kt:7:1:10:1 | <init> |
 | methods2.kt:7:1:10:1 | equals |

java/ql/test/kotlin/library-tests/variables/variables.expected

@@ -1,5 +1,3 @@
-| file://:0:0:0:0 | other | file://:0:0:0:0 | Any | file://:0:0:0:0 | <none> |
-| file://:0:0:0:0 | other | file://:0:0:0:0 | Any | file://:0:0:0:0 | <none> |
 | variables.kt:2:1:8:1 | other | file://:0:0:0:0 | Any | file://:0:0:0:0 | <none> |
 | variables.kt:3:5:3:21 | prop | file://:0:0:0:0 | int | file://:0:0:0:0 | <none> |
 | variables.kt:5:20:5:29 | param | file://:0:0:0:0 | int | file://:0:0:0:0 | <none> |