Merge pull request github#80 from github/igfoo/more

Kotlin: Extract type aliases

Author: igfoo

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

@@ -411,6 +411,10 @@ open class KotlinUsesExtractor(
     }
 
     fun useSimpleType(s: IrSimpleType, canReturnPrimitiveTypes: Boolean): TypeResults {
+        if (s.abbreviation != null) {
+            // TODO: Extract this information
+            logger.warn(Severity.ErrorSevere, "Type alias ignored for " + s.render())
+        }
         // We use this when we don't actually have an IrClass for a class
         // we want to refer to
         fun makeClass(pkgName: String, className: String): Label<DbClass> {
@@ -765,6 +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)
     }
@@ -789,6 +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)
         }
     }
@@ -1027,6 +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)

java/kotlin-extractor/src/main/kotlin/utils/Logger.kt

@@ -33,6 +33,20 @@ open class Logger(val logCounter: LogCounter, open val tw: TrapWriter) {
         return "[${SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Date())} K]"
     }
 
+    private fun getWarningLocation(): String? {
+        val st = Exception().stackTrace
+        for(x in st) {
+            when(x.className) {
+                "com.github.codeql.Logger",
+                "com.github.codeql.FileLogger" -> {}
+                else -> {
+                    return x.toString()
+                }
+            }
+        }
+        return null
+    }
+
     fun flush() {
         tw.flush()
         System.out.flush()
@@ -53,26 +67,26 @@ open class Logger(val logCounter: LogCounter, open val tw: TrapWriter) {
     fun trace(msg: String, exn: Exception) {
         trace(msg + " // " + exn)
     }
-    fun warn(severity: Severity, msg: String, locationString: String? = null, locationId: Label<DbLocation> = tw.unknownLocation, stackIndex: Int = 2) {
-        val st = Exception().stackTrace
+    fun warn(severity: Severity, msg: String, locationString: String? = null, locationId: Label<DbLocation> = tw.unknownLocation) {
+        val warningLoc = getWarningLocation()
+        val warningLocStr = if(warningLoc == null) "<unknown location>" else warningLoc
         val suffix =
-            if(st.size < stackIndex + 1) {
+            if(warningLoc == null) {
                 "    Missing caller information.\n"
             } else {
-                val caller = st[stackIndex].toString()
-                val count = logCounter.warningCounts.getOrDefault(caller, 0) + 1
-                logCounter.warningCounts[caller] = count
+                val count = logCounter.warningCounts.getOrDefault(warningLoc, 0) + 1
+                logCounter.warningCounts[warningLoc] = count
                 when {
                     logCounter.warningLimit <= 0 -> ""
-                    count == logCounter.warningLimit -> "    Limit reached for warnings from $caller.\n"
+                    count == logCounter.warningLimit -> "    Limit reached for warnings from $warningLoc.\n"
                     count > logCounter.warningLimit -> return
                     else -> ""
                 }
             }
         val ts = timestamp()
         tw.writeDiagnostics(StarLabel(), severity.sev, "", msg, "$ts $msg\n$suffix", locationId)
         val locStr = if (locationString == null) "" else "At " + locationString + ": "
-        print("$ts Warning: $locStr$msg\n$suffix")
+        print("$ts Warning($warningLocStr): $locStr$msg\n$suffix")
     }
     fun warn(msg: String, exn: Exception) {
         warn(Severity.Warn, msg + " // " + exn)
@@ -102,9 +116,9 @@ class FileLogger(logCounter: LogCounter, override val tw: FileTrapWriter): Logge
         return "[${SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Date())} K]"
     }
 
-    fun warnElement(severity: Severity, msg: String, element: IrElement, stackIndex: Int = 3) {
+    fun warnElement(severity: Severity, msg: String, element: IrElement) {
         val locationString = tw.getLocationString(element)
         val locationId = tw.getLocation(element)
-        warn(severity, msg, locationString, locationId, stackIndex)
+        warn(severity, msg, locationString, locationId)
     }
 }

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(
@@ -926,19 +932,22 @@ 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;
 

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, _)
 }
 
 /**

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)
+  }
+}

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

@@ -0,0 +1,16 @@
+
+class MyClass<T> {}
+
+typealias AliasInt = Int
+typealias AliasX = MyClass<Int>
+typealias AliasY = MyClass<AliasInt>
+
+fun someFun(
+    x1: Int,
+    x2: AliasInt,
+    x3: MyClass<Int>,
+    x4: AliasX,
+    x5: MyClass<AliasInt>,
+    x6: AliasY) {
+}
+

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

@@ -0,0 +1,3 @@
+| test.kt:4:1:4:24 | AliasInt | file://:0:0:0:0 | Kotlin not-null Int |
+| test.kt:5:1:5:31 | AliasX | file://:0:0:0:0 | Kotlin not-null MyClass |
+| test.kt:6:1:6:36 | AliasY | file://:0:0:0:0 | Kotlin not-null MyClass |

java/ql/test/kotlin/library-tests/type_aliases/type_aliases.ql

@@ -0,0 +1,4 @@
+import java
+
+from KotlinTypeAlias ta
+select ta, ta.getKotlinType()