Merge pull request #131 from github/aibaars/pattern

AST: split method call into normal and setter calls

ql/src/codeql_ruby/ast/Call.qll

@@ -9,32 +9,6 @@ class Call extends Expr {
 
   override string getAPrimaryQlClass() { result = "Call" }
 
-  /**
-   * Gets the receiver of this call, if any. For example:
-   *
-   * ```rb
-   * foo.bar
-   * Baz::qux
-   * corge()
-   * ```
-   *
-   * The result for the call to `bar` is the `Expr` for `foo`; the result for
-   * the call to `qux` is the `Expr` for `Baz`; for the call to `corge` there
-   * is no result.
-   */
-  final Expr getReceiver() { result = range.getReceiver() }
-
-  /**
-   * Gets the name of the method being called. For example, in:
-   *
-   * ```rb
-   * foo.bar x, y
-   * ```
-   *
-   * the result is `"bar"`.
-   */
-  final string getMethodName() { result = range.getMethodName() }
-
   /**
    * Gets the `n`th argument of this method call. In the following example, the
    * result for n=0 is the `IntegerLiteral` 0, while for n=1 the result is a
@@ -44,6 +18,7 @@ class Call extends Expr {
    * `getKeywordArgument(string keyword)` predicate.
    * ```rb
    * foo(0, bar: 1)
+   * yield 0, bar: 1
    * ```
    */
   final Expr getArgument(int n) { result = range.getArgument(n) }
@@ -73,6 +48,41 @@ class Call extends Expr {
    * Gets the number of arguments of this method call.
    */
   final int getNumberOfArguments() { result = count(this.getAnArgument()) }
+}
+
+/**
+ * A method call.
+ */
+class MethodCall extends Call {
+  override MethodCall::Range range;
+
+  override string getAPrimaryQlClass() { result = "MethodCall" }
+
+  /**
+   * Gets the receiver of this call, if any. For example:
+   *
+   * ```rb
+   * foo.bar
+   * Baz::qux
+   * corge()
+   * ```
+   *
+   * The result for the call to `bar` is the `Expr` for `foo`; the result for
+   * the call to `qux` is the `Expr` for `Baz`; for the call to `corge` there
+   * is no result.
+   */
+  final Expr getReceiver() { result = range.getReceiver() }
+
+  /**
+   * Gets the name of the method being called. For example, in:
+   *
+   * ```rb
+   * foo.bar x, y
+   * ```
+   *
+   * the result is `"bar"`.
+   */
+  final string getMethodName() { result = range.getMethodName() }
 
   /**
    * Gets the block of this method call, if any.
@@ -83,13 +93,26 @@ class Call extends Expr {
   final Block getBlock() { result = range.getBlock() }
 }
 
+/**
+ * A call to a setter method.
+ * ```rb
+ * self.foo = 10
+ * a[0] = 10
+ * ```
+ */
+class SetterMethodCall extends MethodCall, LhsExpr {
+  final override SetterMethodCall::Range range;
+
+  final override string getAPrimaryQlClass() { result = "SetterMethodCall" }
+}
+
 /**
  * An element reference; a call to the `[]` method.
  * ```rb
  * a[0]
  * ```
  */
-class ElementReference extends Call, @element_reference {
+class ElementReference extends MethodCall, @element_reference {
   final override ElementReference::Range range;
 
   final override string getAPrimaryQlClass() { result = "ElementReference" }
@@ -117,7 +140,7 @@ class YieldCall extends Call, @yield {
  * end
  * ```
  */
-class SuperCall extends Call {
+class SuperCall extends MethodCall {
   final override SuperCall::Range range;
 
   final override string getAPrimaryQlClass() { result = "SuperCall" }

ql/src/codeql_ruby/ast/internal/Call.qll

@@ -1,64 +1,100 @@
 private import codeql_ruby.AST
 private import codeql_ruby.ast.internal.AST
 private import codeql_ruby.ast.internal.Expr
+private import codeql_ruby.ast.internal.Pattern
 private import codeql_ruby.ast.internal.TreeSitter
 private import codeql_ruby.ast.internal.Variable
 
 module Call {
   abstract class Range extends Expr::Range {
-    abstract Expr getReceiver();
+    abstract Expr getArgument(int n);
+
+    override predicate child(string label, AstNode::Range child) {
+      label = "getArgument" and child = getArgument(_)
+    }
+  }
+}
+
+module MethodCall {
+  class Range extends Call::Range {
+    MethodCallRange::Range range;
+
+    Range() { this = range }
+
+    final Block getBlock() { result = range.getBlock() }
+
+    final Expr getReceiver() { result = range.getReceiver() }
+
+    final override Expr getArgument(int n) { result = range.getArgument(n) }
 
     abstract string getMethodName();
 
-    abstract Expr getArgument(int n);
-
-    abstract Block getBlock();
-
-    override string toString() { result = "call to " + this.getMethodName() }
+    override string toString() {
+      result = range.toString()
+      or
+      not exists(range.toString()) and result = "call to " + concat(this.getMethodName(), "/")
+    }
 
     final override predicate child(string label, AstNode::Range child) {
-      label = "getReceiver" and child = getReceiver()
+      super.child(label, child)
       or
-      label = "getArgument" and child = getArgument(_)
+      label = "getReceiver" and child = getReceiver()
       or
       label = "getBlock" and child = getBlock()
     }
   }
+}
 
-  private class IdentifierCallRange extends Call::Range, @token_identifier {
+module MethodCallRange {
+  abstract class Range extends @ast_node {
+    Generated::AstNode generated;
+
+    Range() { this = generated }
+
+    abstract Block getBlock();
+
+    abstract Expr getReceiver();
+
+    abstract string getMethod();
+
+    abstract Expr getArgument(int n);
+
+    string toString() { none() }
+  }
+
+  private class IdentifierCallRange extends MethodCallRange::Range, @token_identifier {
     final override Generated::Identifier generated;
 
     IdentifierCallRange() { vcall(this) and not access(this, _) }
 
     final override Expr getReceiver() { none() }
 
-    final override string getMethodName() { result = generated.getValue() }
+    final override string getMethod() { result = generated.getValue() }
 
     final override Expr getArgument(int n) { none() }
 
     final override Block getBlock() { none() }
   }
 
-  private class ScopeResolutionIdentifierCallRange extends Call::Range, @scope_resolution {
+  private class ScopeResolutionIdentifierCallRange extends MethodCallRange::Range, @scope_resolution {
     final override Generated::ScopeResolution generated;
     Generated::Identifier identifier;
 
     ScopeResolutionIdentifierCallRange() {
       identifier = generated.getName() and
-      vcall(this) and
-      not access(identifier, _)
+      not exists(Generated::Call c | c.getMethod() = this)
     }
 
     final override Expr getReceiver() { result = generated.getScope() }
 
-    final override string getMethodName() { result = identifier.getValue() }
+    final override string getMethod() { result = identifier.getValue() }
 
     final override Expr getArgument(int n) { none() }
 
     final override Block getBlock() { none() }
   }
 
-  private class RegularCallRange extends Call::Range, @call {
+  private class RegularCallRange extends MethodCallRange::Range, @call {
     final override Generated::Call generated;
 
     final override Expr getReceiver() {
@@ -68,25 +104,33 @@ module Call {
       result = generated.getMethod().(Generated::ScopeResolution).getScope()
     }
 
-    final override string getMethodName() {
-      result = generated.getMethod().(Generated::Token).getValue() or
+    final override string getMethod() {
+      result = "call" and generated.getMethod() instanceof Generated::ArgumentList
+      or
+      result = generated.getMethod().(Generated::Token).getValue()
+      or
       result =
         generated.getMethod().(Generated::ScopeResolution).getName().(Generated::Token).getValue()
     }
 
-    final override Expr getArgument(int n) { result = generated.getArguments().getChild(n) }
+    final override Expr getArgument(int n) {
+      result = generated.getArguments().getChild(n)
+      or
+      not exists(generated.getArguments()) and
+      result = generated.getMethod().(Generated::ArgumentList).getChild(n)
+    }
 
     final override Block getBlock() { result = generated.getBlock() }
   }
 }
 
-module ElementReference {
-  class Range extends Call::Range, @element_reference {
+module ElementReferenceRange {
+  class Range extends MethodCallRange::Range, @element_reference {
     final override Generated::ElementReference generated;
 
     final override Expr getReceiver() { result = generated.getObject() }
 
-    final override string getMethodName() { result = "[]" }
+    final override string getMethod() { result = "[]" }
 
     final override string toString() { result = "...[...]" }
 
@@ -96,24 +140,53 @@ module ElementReference {
   }
 }
 
-module YieldCall {
-  class Range extends Call::Range, @yield {
-    final override Generated::Yield generated;
+module NormalMethodCall {
+  class Range extends MethodCall::Range {
+    Range() {
+      not this instanceof LhsExpr::Range or
+      generated.getParent() instanceof AssignOperation
+    }
 
-    final override Expr getReceiver() { none() }
+    final override string getMethodName() { result = range.getMethod() }
+  }
+}
 
-    final override string getMethodName() { result = "yield" }
+module SetterMethodCall {
+  class Range extends MethodCall::Range, LhsExpr::Range {
+    final override string getMethodName() { result = range.getMethod() + "=" }
 
-    final override Expr getArgument(int n) { result = generated.getChild().getChild(n) }
+    final override string toString() { result = MethodCall::Range.super.toString() }
+  }
+}
 
-    final override Block getBlock() { none() }
+module ElementReference {
+  class Range extends MethodCall::Range {
+    override ElementReferenceRange::Range range;
+
+    final override string getMethodName() { none() }
   }
 }
 
 module SuperCall {
-  abstract class Range extends Call::Range { }
+  class Range extends NormalMethodCall::Range {
+    override SuperCallRange::Range range;
+  }
+}
 
-  private class SuperTokenCallRange extends SuperCall::Range, @token_super {
+module YieldCall {
+  class Range extends Call::Range, @yield {
+    final override Generated::Yield generated;
+
+    final override Expr getArgument(int n) { result = generated.getChild().getChild(n) }
+
+    final override string toString() { result = "yield ..." }
+  }
+}
+
+module SuperCallRange {
+  abstract class Range extends MethodCallRange::Range { }
+
+  private class SuperTokenCallRange extends SuperCallRange::Range, @token_super {
     final override Generated::Super generated;
 
     // N.B. `super` tokens can never be accesses, so any vcall with `super` must
@@ -122,21 +195,21 @@ module SuperCall {
 
     final override Expr getReceiver() { none() }
 
-    final override string getMethodName() { result = generated.getValue() }
+    final override string getMethod() { result = generated.getValue() }
 
     final override Expr getArgument(int n) { none() }
 
     final override Block getBlock() { none() }
   }
 
-  private class RegularSuperCallRange extends SuperCall::Range, @call {
+  private class RegularSuperCallRange extends SuperCallRange::Range, @call {
     final override Generated::Call generated;
 
     RegularSuperCallRange() { generated.getMethod() instanceof Generated::Super }
 
     final override Expr getReceiver() { none() }
 
-    final override string getMethodName() {
+    final override string getMethod() {
       result = generated.getMethod().(Generated::Super).getValue()
     }