Merge pull request #357 from github/erik-krogh/fix-implicit-this

Add explicit `this` qualifiers

ql/lib/codeql/Locations.qll

@@ -25,12 +25,12 @@ class Location extends @location {
   int getEndColumn() { locations_default(this, _, _, _, _, result) }
 
   /** Gets the number of lines covered by this location. */
-  int getNumLines() { result = getEndLine() - getStartLine() + 1 }
+  int getNumLines() { result = this.getEndLine() - this.getStartLine() + 1 }
 
   /** Gets a textual representation of this element. */
   string toString() {
     exists(string filepath, int startline, int startcolumn, int endline, int endcolumn |
-      hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) and
+      this.hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn) and
       result = filepath + "@" + startline + ":" + startcolumn + ":" + endline + ":" + endcolumn
     )
   }

ql/lib/codeql/files/FileSystem.qll

@@ -8,10 +8,10 @@ abstract class Container extends @container {
   Container getAChildContainer() { this = result.getParentContainer() }
 
   /** Gets a file in this container. */
-  File getAFile() { result = getAChildContainer() }
+  File getAFile() { result = this.getAChildContainer() }
 
   /** Gets a sub-folder in this container. */
-  Folder getAFolder() { result = getAChildContainer() }
+  Folder getAFolder() { result = this.getAChildContainer() }
 
   /**
    * Gets the absolute, canonical path of this container, using forward slashes
@@ -57,7 +57,7 @@ abstract class Container extends @container {
    * </table>
    */
   string getBaseName() {
-    result = getAbsolutePath().regexpCapture(".*/(([^/]*?)(?:\\.([^.]*))?)", 1)
+    result = this.getAbsolutePath().regexpCapture(".*/(([^/]*?)(?:\\.([^.]*))?)", 1)
   }
 
   /**
@@ -83,17 +83,19 @@ abstract class Container extends @container {
    * <tr><td>"/tmp/x.tar.gz"</td><td>"gz"</td></tr>
    * </table>
    */
-  string getExtension() { result = getAbsolutePath().regexpCapture(".*/([^/]*?)(\\.([^.]*))?", 3) }
+  string getExtension() {
+    result = this.getAbsolutePath().regexpCapture(".*/([^/]*?)(\\.([^.]*))?", 3)
+  }
 
   /** Gets the file in this container that has the given `baseName`, if any. */
   File getFile(string baseName) {
-    result = getAFile() and
+    result = this.getAFile() and
     result.getBaseName() = baseName
   }
 
   /** Gets the sub-folder in this container that has the given `baseName`, if any. */
   Folder getFolder(string baseName) {
-    result = getAFolder() and
+    result = this.getAFolder() and
     result.getBaseName() = baseName
   }
 
@@ -110,7 +112,7 @@ abstract class Container extends @container {
    */
   string getRelativePath() {
     exists(string absPath, string pref |
-      absPath = getAbsolutePath() and sourceLocationPrefix(pref)
+      absPath = this.getAbsolutePath() and sourceLocationPrefix(pref)
     |
       absPath = pref and result = ""
       or
@@ -136,7 +138,9 @@ abstract class Container extends @container {
    * <tr><td>"/tmp/x.tar.gz"</td><td>"x.tar"</td></tr>
    * </table>
    */
-  string getStem() { result = getAbsolutePath().regexpCapture(".*/([^/]*?)(?:\\.([^.]*))?", 1) }
+  string getStem() {
+    result = this.getAbsolutePath().regexpCapture(".*/([^/]*?)(?:\\.([^.]*))?", 1)
+  }
 
   /**
    * Gets a URL representing the location of this container.
@@ -150,7 +154,7 @@ abstract class Container extends @container {
    *
    * This is the absolute path of the container.
    */
-  string toString() { result = getAbsolutePath() }
+  string toString() { result = this.getAbsolutePath() }
 }
 
 /** A folder. */
@@ -158,7 +162,7 @@ class Folder extends Container, @folder {
   override string getAbsolutePath() { folders(this, result) }
 
   /** Gets the URL of this folder. */
-  override string getURL() { result = "folder://" + getAbsolutePath() }
+  override string getURL() { result = "folder://" + this.getAbsolutePath() }
 }
 
 /** A file. */

ql/lib/codeql/ruby/ApiGraphs.qll

@@ -47,7 +47,7 @@ module API {
      * Gets a call to a method on the receiver represented by this API component.
      */
     DataFlow::CallNode getAMethodCall(string method) {
-      result = getReturn(method).getAnImmediateUse()
+      result = this.getReturn(method).getAnImmediateUse()
     }
 
     /**
@@ -60,21 +60,21 @@ module API {
      */
     bindingset[m]
     bindingset[result]
-    Node getMember(string m) { result = getASuccessor(Label::member(m)) }
+    Node getMember(string m) { result = this.getASuccessor(Label::member(m)) }
 
     /**
      * Gets a node representing a member of this API component where the name of the member is
      * not known statically.
      */
-    Node getUnknownMember() { result = getASuccessor(Label::unknownMember()) }
+    Node getUnknownMember() { result = this.getASuccessor(Label::unknownMember()) }
 
     /**
      * Gets a node representing a member of this API component where the name of the member may
      * or may not be known statically.
      */
     Node getAMember() {
-      result = getASuccessor(Label::member(_)) or
-      result = getUnknownMember()
+      result = this.getASuccessor(Label::member(_)) or
+      result = this.getUnknownMember()
     }
 
     /**
@@ -88,28 +88,30 @@ module API {
      * This predicate may have multiple results when there are multiple constructor calls invoking this API component.
      * Consider using `getAnInstantiation()` if there is a need to distinguish between individual constructor calls.
      */
-    Node getInstance() { result = getASuccessor(Label::instance()) }
+    Node getInstance() { result = this.getASuccessor(Label::instance()) }
 
     /**
      * Gets a node representing the result of calling a method on the receiver represented by this node.
      */
-    Node getReturn(string method) { result = getASuccessor(Label::return(method)) }
+    Node getReturn(string method) { result = this.getASuccessor(Label::return(method)) }
 
     /**
      * Gets a `new` call to the function represented by this API component.
      */
-    DataFlow::Node getAnInstantiation() { result = getInstance().getAnImmediateUse() }
+    DataFlow::Node getAnInstantiation() { result = this.getInstance().getAnImmediateUse() }
 
     /**
      * Gets a node representing a subclass of the class represented by this node.
      */
-    Node getASubclass() { result = getASuccessor(Label::subclass()) }
+    Node getASubclass() { result = this.getASuccessor(Label::subclass()) }
 
     /**
      * Gets a string representation of the lexicographically least among all shortest access paths
      * from the root to this node.
      */
-    string getPath() { result = min(string p | p = getAPath(Impl::distanceFromRoot(this)) | p) }
+    string getPath() {
+      result = min(string p | p = this.getAPath(Impl::distanceFromRoot(this)) | p)
+    }
 
     /**
      * Gets a node such that there is an edge in the API graph between this node and the other
@@ -127,13 +129,13 @@ module API {
      * Gets a node such that there is an edge in the API graph between this node and the other
      * one.
      */
-    Node getAPredecessor() { result = getAPredecessor(_) }
+    Node getAPredecessor() { result = this.getAPredecessor(_) }
 
     /**
      * Gets a node such that there is an edge in the API graph between that other node and
      * this one.
      */
-    Node getASuccessor() { result = getASuccessor(_) }
+    Node getASuccessor() { result = this.getASuccessor(_) }
 
     /**
      * Gets the data-flow node that gives rise to this node, if any.
@@ -146,7 +148,7 @@ module API {
       or
       // For nodes that do not have a meaningful location, `path` is the empty string and all other
       // parameters are zero.
-      not exists(getInducingNode()) and
+      not exists(this.getInducingNode()) and
       result instanceof EmptyLocation
     }
 
@@ -189,7 +191,7 @@ module API {
   class Use extends Node, Impl::MkUse {
     override string toString() {
       exists(string type | type = "Use " |
-        result = type + getPath()
+        result = type + this.getPath()
         or
         not exists(this.getPath()) and result = type + "with no path"
       )

ql/lib/codeql/ruby/ast/Control.qll

@@ -184,9 +184,9 @@ class UnlessExpr extends ConditionalExpr, TUnlessExpr {
   final Stmt getElse() { toGenerated(result) = g.getAlternative() }
 
   final override Expr getBranch(boolean cond) {
-    cond = false and result = getThen()
+    cond = false and result = this.getThen()
     or
-    cond = true and result = getElse()
+    cond = true and result = this.getElse()
   }
 
   final override string toString() { result = "unless ..." }
@@ -292,9 +292,9 @@ class TernaryIfExpr extends ConditionalExpr, TTernaryIfExpr {
   final Stmt getElse() { toGenerated(result) = g.getAlternative() }
 
   final override Stmt getBranch(boolean cond) {
-    cond = true and result = getThen()
+    cond = true and result = this.getThen()
     or
-    cond = false and result = getElse()
+    cond = false and result = this.getElse()
   }
 
   final override string toString() { result = "... ? ... : ..." }
@@ -349,10 +349,10 @@ class CaseExpr extends ControlExpr, TCaseExpr {
   final Expr getABranch() { result = this.getBranch(_) }
 
   /** Gets a `when` branch of this case expression. */
-  final WhenExpr getAWhenBranch() { result = getABranch() }
+  final WhenExpr getAWhenBranch() { result = this.getABranch() }
 
   /** Gets the `else` branch of this case expression, if any. */
-  final StmtSequence getElseBranch() { result = getABranch() }
+  final StmtSequence getElseBranch() { result = this.getABranch() }
 
   /**
    * Gets the number of branches of this case expression.

ql/lib/codeql/ruby/ast/Expr.qll

@@ -183,7 +183,7 @@ class BodyStmt extends StmtSequence, TBodyStmt {
   /** Gets the `n`th rescue clause in this block. */
   final RescueClause getRescue(int n) {
     result =
-      rank[n + 1](RescueClause node, int i | toGenerated(node) = getChild(i) | node order by i)
+      rank[n + 1](RescueClause node, int i | toGenerated(node) = this.getChild(i) | node order by i)
   }
 
   /** Gets a rescue clause in this block. */

ql/lib/codeql/ruby/ast/Literal.qll

@@ -631,7 +631,7 @@ class HereDoc extends StringlikeLiteral, THereDoc {
    * COMMAND
    * ```
    */
-  final predicate isSubShell() { getQuoteStyle() = "`" }
+  final predicate isSubShell() { this.getQuoteStyle() = "`" }
 
   /**
    * Gets the quotation mark (`"`, `'` or `` ` ``) that surrounds the here document identifier, if any.

ql/lib/codeql/ruby/ast/Module.qll

@@ -125,7 +125,7 @@ class Toplevel extends ModuleBase, TToplevel {
   /**
    * Gets a `BEGIN` block.
    */
-  final BeginBlock getABeginBlock() { result = getBeginBlock(_) }
+  final BeginBlock getABeginBlock() { result = this.getBeginBlock(_) }
 
   final override AstNode getAChild(string pred) {
     result = super.getAChild(pred)

ql/lib/codeql/ruby/ast/Operation.qll

@@ -453,9 +453,9 @@ class Assignment extends Operation instanceof AssignmentImpl {
   override AstNode getAChild(string pred) {
     result = Operation.super.getAChild(pred)
     or
-    pred = "getLeftOperand" and result = getLeftOperand()
+    pred = "getLeftOperand" and result = this.getLeftOperand()
     or
-    pred = "getRightOperand" and result = getRightOperand()
+    pred = "getRightOperand" and result = this.getRightOperand()
   }
 }
 

ql/lib/codeql/ruby/ast/Pattern.qll

@@ -92,5 +92,5 @@ class TuplePattern extends Pattern, TTuplePattern {
 
   override string toString() { result = "(..., ...)" }
 
-  override AstNode getAChild(string pred) { pred = "getElement" and result = getElement(_) }
+  override AstNode getAChild(string pred) { pred = "getElement" and result = this.getElement(_) }
 }

ql/lib/codeql/ruby/ast/Statement.qll

@@ -97,7 +97,7 @@ class UndefStmt extends Stmt, TUndefStmt {
   final MethodName getMethodName(int n) { toGenerated(result) = g.getChild(n) }
 
   /** Gets a method name to undefine. */
-  final MethodName getAMethodName() { result = getMethodName(_) }
+  final MethodName getAMethodName() { result = this.getMethodName(_) }
 
   final override string getAPrimaryQlClass() { result = "UndefStmt" }
 

ql/lib/codeql/ruby/controlflow/BasicBlocks.qll

@@ -147,7 +147,7 @@ class BasicBlock extends TBasicBlockStart {
    */
   predicate inDominanceFrontier(BasicBlock df) {
     this.dominatesPredecessor(df) and
-    not strictlyDominates(df)
+    not this.strictlyDominates(df)
   }
 
   /**
@@ -373,7 +373,7 @@ private module JoinBlockPredecessors {
 
 /** A basic block with more than one predecessor. */
 class JoinBlock extends BasicBlock {
-  JoinBlock() { getFirstNode().isJoin() }
+  JoinBlock() { this.getFirstNode().isJoin() }
 
   /**
    * Gets the `i`th predecessor of this join block, with respect to some

ql/lib/codeql/ruby/controlflow/ControlFlowGraph.qll

@@ -98,7 +98,7 @@ module SuccessorTypes {
     /** Gets the Boolean value of this successor. */
     final boolean getValue() { result = value }
 
-    override string toString() { result = getValue().toString() }
+    override string toString() { result = this.getValue().toString() }
   }
 
   /**

ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll

@@ -241,7 +241,7 @@ module Trees {
       c instanceof NormalCompletion
       or
       // Flow into `ensure` block
-      pred = getAnEnsurePredecessor(c, true) and
+      pred = this.getAnEnsurePredecessor(c, true) and
       first(this.getEnsure(), succ)
     }
 

ql/lib/codeql/ruby/controlflow/internal/Splitting.qll

@@ -244,7 +244,7 @@ module EnsureSplitting {
      */
     private predicate exit(Trees::BodyStmtTree block, AstNode pred, Completion c, boolean inherited) {
       exists(EnsureSplitType type |
-        exit0(pred, block, this.getNestLevel(), c) and
+        this.exit0(pred, block, this.getNestLevel(), c) and
         type = this.getType()
       |
         if last(block.getEnsure(), pred, c)
@@ -303,18 +303,18 @@ module EnsureSplitting {
     override predicate hasExit(AstNode pred, AstNode succ, Completion c) {
       succ(pred, succ, c) and
       (
-        exit(_, pred, c, _)
+        this.exit(_, pred, c, _)
         or
-        exit(_, pred, c.(NestedBreakCompletion).getAnInnerCompatibleCompletion(), _)
+        this.exit(_, pred, c.(NestedBreakCompletion).getAnInnerCompatibleCompletion(), _)
       )
     }
 
     override predicate hasExitScope(CfgScope scope, AstNode last, Completion c) {
       succExit(scope, last, c) and
       (
-        exit(_, last, c, _)
+        this.exit(_, last, c, _)
         or
-        exit(_, last, c.(NestedBreakCompletion).getAnInnerCompatibleCompletion(), _)
+        this.exit(_, last, c.(NestedBreakCompletion).getAnInnerCompatibleCompletion(), _)
       )
     }
 

ql/lib/codeql/ruby/dataflow/internal/DataFlowPrivate.qll

@@ -373,15 +373,15 @@ private module ParameterNodes {
     override CfgScope getCfgScope() { result = method }
 
     override Location getLocationImpl() {
-      result = getParameter().getLocation()
+      result = this.getParameter().getLocation()
       or
-      not exists(getParameter()) and result = method.getLocation()
+      not exists(this.getParameter()) and result = method.getLocation()
     }
 
     override string toStringImpl() {
-      result = getParameter().toString()
+      result = this.getParameter().toString()
       or
-      not exists(getParameter()) and result = "&block"
+      not exists(this.getParameter()) and result = "&block"
     }
   }
 

ql/lib/codeql/ruby/dataflow/internal/DataFlowPublic.qll

@@ -37,7 +37,7 @@ class Node extends TNode {
   predicate hasLocationInfo(
     string filepath, int startline, int startcolumn, int endline, int endcolumn
   ) {
-    getLocation().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
+    this.getLocation().hasLocationInfo(filepath, startline, startcolumn, endline, endcolumn)
   }
 
   /**

ql/lib/codeql/ruby/frameworks/StandardLibrary.qll

@@ -126,7 +126,7 @@ class SubshellLiteralExecution extends SystemCommandExecution::Range {
 
   override DataFlow::Node getAnArgument() { result.asExpr().getExpr() = literal.getComponent(_) }
 
-  override predicate isShellInterpreted(DataFlow::Node arg) { arg = getAnArgument() }
+  override predicate isShellInterpreted(DataFlow::Node arg) { arg = this.getAnArgument() }
 }
 
 /**
@@ -145,7 +145,7 @@ class SubshellHeredocExecution extends SystemCommandExecution::Range {
 
   override DataFlow::Node getAnArgument() { result.asExpr().getExpr() = heredoc.getComponent(_) }
 
-  override predicate isShellInterpreted(DataFlow::Node arg) { arg = getAnArgument() }
+  override predicate isShellInterpreted(DataFlow::Node arg) { arg = this.getAnArgument() }
 }
 
 /**
@@ -182,7 +182,7 @@ class KernelSystemCall extends SystemCommandExecution::Range, KernelMethodCall {
 
   override predicate isShellInterpreted(DataFlow::Node arg) {
     // Kernel.system invokes a subshell if you provide a single string as argument
-    this.getNumberOfArguments() = 1 and arg = getAnArgument()
+    this.getNumberOfArguments() = 1 and arg = this.getAnArgument()
   }
 }
 
@@ -198,7 +198,7 @@ class KernelExecCall extends SystemCommandExecution::Range, KernelMethodCall {
 
   override predicate isShellInterpreted(DataFlow::Node arg) {
     // Kernel.exec invokes a subshell if you provide a single string as argument
-    this.getNumberOfArguments() = 1 and arg = getAnArgument()
+    this.getNumberOfArguments() = 1 and arg = this.getAnArgument()
   }
 }
 
@@ -219,7 +219,7 @@ class KernelSpawnCall extends SystemCommandExecution::Range, KernelMethodCall {
 
   override predicate isShellInterpreted(DataFlow::Node arg) {
     // Kernel.spawn invokes a subshell if you provide a single string as argument
-    this.getNumberOfArguments() = 1 and arg = getAnArgument()
+    this.getNumberOfArguments() = 1 and arg = this.getAnArgument()
   }
 }
 

ql/lib/codeql/ruby/frameworks/XmlParsing.qll

@@ -72,7 +72,7 @@ private newtype TFeature =
 class Feature extends TFeature {
   abstract int getValue();
 
-  string toString() { result = getConstantName() }
+  string toString() { result = this.getConstantName() }
 
   abstract string getConstantName();
 }

ql/lib/codeql/ruby/printAst.qll

@@ -76,7 +76,7 @@ class PrintAstNode extends TPrintNode {
   PrintAstNode getChild(string edgeName) { none() }
 
   /** Gets a child of this node. */
-  final PrintAstNode getAChild() { result = getChild(_) }
+  final PrintAstNode getAChild() { result = this.getChild(_) }
 
   /** Gets the parent of this node, if any. */
   final PrintAstNode getParent() { result.getAChild() = this }

ql/lib/codeql/ruby/regexp/ParseRegExp.qll

@@ -229,8 +229,8 @@ class RegExp extends AST::RegExpLiteral {
 
   /** Matches named character properties such as `\p{Word}` and `[[:digit:]]` */
   predicate namedCharacterProperty(int start, int end, string name) {
-    pStyleNamedCharacterProperty(start, end, name) or
-    posixStyleNamedCharacterProperty(start, end, name)
+    this.pStyleNamedCharacterProperty(start, end, name) or
+    this.posixStyleNamedCharacterProperty(start, end, name)
   }
 
   /** Gets the name of the character property in start,end */

ql/lib/codeql/ruby/regexp/ReDoSUtil.qll

@@ -143,7 +143,7 @@ class RegExpRoot extends RegExpTerm {
     // there are no lookbehinds
     not exists(RegExpLookbehind lbh | getRoot(lbh) = this) and
     // is actually used as a RegExp
-    isUsedAsRegExp() //and
+    this.isUsedAsRegExp() //and
     // // pragmatic performance optimization: ignore minified files.
     // not getRootTerm().getParent().(Expr).getTopLevel().isMinified()
   }
@@ -277,7 +277,7 @@ abstract private class CharacterClass extends InputSymbol {
   /**
    * Gets a character matched by this character class.
    */
-  string choose() { result = getARelevantChar() and matches(result) }
+  string choose() { result = this.getARelevantChar() and this.matches(result) }
 }
 
 /**

ql/lib/codeql/ruby/regexp/RegExpTreeView.qll

@@ -12,9 +12,9 @@ class RegExpParent extends TRegExpParent {
 
   RegExpTerm getChild(int i) { none() }
 
-  RegExpTerm getAChild() { result = getChild(_) }
+  RegExpTerm getAChild() { result = this.getChild(_) }
 
-  int getNumChild() { result = count(getAChild()) }
+  int getNumChild() { result = count(this.getAChild()) }
 
   /**
    * Gets the name of a primary CodeQL class to which this regular
@@ -72,7 +72,7 @@ class RegExpTerm extends RegExpParent {
   RegExpTerm getRootTerm() {
     this.isRootTerm() and result = this
     or
-    result = getParent().(RegExpTerm).getRootTerm()
+    result = this.getParent().(RegExpTerm).getRootTerm()
   }
 
   predicate isUsedAsRegExp() { any() }
@@ -137,7 +137,7 @@ class RegExpTerm extends RegExpParent {
 
   /** Gets the regular expression term that is matched (textually) before this one, if any. */
   RegExpTerm getPredecessor() {
-    exists(RegExpTerm parent | parent = getParent() |
+    exists(RegExpTerm parent | parent = this.getParent() |
       result = parent.(RegExpSequence).previousElement(this)
       or
       not exists(parent.(RegExpSequence).previousElement(this)) and
@@ -148,7 +148,7 @@ class RegExpTerm extends RegExpParent {
 
   /** Gets the regular expression term that is matched (textually) after this one, if any. */
   RegExpTerm getSuccessor() {
-    exists(RegExpTerm parent | parent = getParent() |
+    exists(RegExpTerm parent | parent = this.getParent() |
       result = parent.(RegExpSequence).nextElement(this)
       or
       not exists(parent.(RegExpSequence).nextElement(this)) and
@@ -255,7 +255,7 @@ class RegExpSequence extends RegExpTerm, TRegExpSequence {
   override RegExpTerm getChild(int i) { result = seqChild(re, start, end, i) }
 
   /** Gets the element preceding `element` in this sequence. */
-  RegExpTerm previousElement(RegExpTerm element) { element = nextElement(result) }
+  RegExpTerm previousElement(RegExpTerm element) { element = this.nextElement(result) }
 
   /** Gets the element following `element` in this sequence. */
   RegExpTerm nextElement(RegExpTerm element) {
@@ -335,8 +335,8 @@ class RegExpEscape extends RegExpNormalChar {
     or
     this.getUnescaped() = "t" and result = "\t"
     or
-    isUnicode() and
-    result = getUnicode()
+    this.isUnicode() and
+    result = this.getUnicode()
   }
 
   predicate isIdentityEscape() { not this.getUnescaped() in ["n", "r", "t"] }
@@ -349,14 +349,14 @@ class RegExpEscape extends RegExpNormalChar {
   /**
    * Holds if this is a unicode escape.
    */
-  private predicate isUnicode() { getText().prefix(2) = ["\\u", "\\U"] }
+  private predicate isUnicode() { this.getText().prefix(2) = ["\\u", "\\U"] }
 
   /**
    * Gets the unicode char for this escape.
    * E.g. for `\u0061` this returns "a".
    */
   private string getUnicode() {
-    exists(int codepoint | codepoint = sum(getHexValueFromUnicode(_)) |
+    exists(int codepoint | codepoint = sum(this.getHexValueFromUnicode(_)) |
       result = codepoint.toUnicode()
     )
   }
@@ -366,8 +366,8 @@ class RegExpEscape extends RegExpNormalChar {
    * E.g. for `\u0061` and `index = 2` this returns 96 (the number `6` interpreted as hex).
    */
   private int getHexValueFromUnicode(int index) {
-    isUnicode() and
-    exists(string hex, string char | hex = getText().suffix(2) |
+    this.isUnicode() and
+    exists(string hex, string char | hex = this.getText().suffix(2) |
       char = hex.charAt(index) and
       result = 16.pow(hex.length() - index - 1) * toHex(char)
     )
@@ -436,13 +436,13 @@ class RegExpCharacterClass extends RegExpTerm, TRegExpCharacterClass {
 
   predicate isUniversalClass() {
     // [^]
-    isInverted() and not exists(getAChild())
+    this.isInverted() and not exists(this.getAChild())
     or
     // [\w\W] and similar
-    not isInverted() and
+    not this.isInverted() and
     exists(string cce1, string cce2 |
-      cce1 = getAChild().(RegExpCharacterClassEscape).getValue() and
-      cce2 = getAChild().(RegExpCharacterClassEscape).getValue()
+      cce1 = this.getAChild().(RegExpCharacterClassEscape).getValue() and
+      cce2 = this.getAChild().(RegExpCharacterClassEscape).getValue()
     |
       cce1 != cce2 and cce1.toLowerCase() = cce2.toLowerCase()
     )