Introduce Parameter::getAVariable()

ql/src/codeql_ruby/ast/Parameter.qll

@@ -21,6 +21,15 @@ class Parameter extends AstNode {
 
   /** Gets the zero-based position of this parameter. */
   final int getPosition() { result = pos }
+
+  /** Gets a variable introduced by this parameter. */
+  Variable getAVariable() { none() }
+
+  /** Gets the variable named `name` introduced by this parameter. */
+  final Variable getVariable(string name) {
+    result = this.getAVariable() and
+    result.getName() = name
+  }
 }
 
 /**
@@ -33,6 +42,10 @@ class PatternParameter extends Parameter, Pattern { }
 /** A parameter defined using a tuple pattern. */
 class TuplePatternParameter extends PatternParameter, TuplePattern {
   final override string describeQlClass() { result = "TuplePatternParameter" }
+
+  final override Variable getAVariable() {
+    result = this.getAnElement+().(VariablePattern).getVariable()
+  }
 }
 
 /** A named parameter. */
@@ -45,6 +58,8 @@ class NamedParameter extends Parameter {
   /** Gets the variable introduced by this parameter. */
   Variable getVariable() { none() }
 
+  final override Variable getAVariable() { result = this.getVariable() }
+
   /** Gets an access to this parameter. */
   final VariableAccess getAnAccess() { result = this.getVariable().getAnAccess() }
 }

ql/src/codeql_ruby/ast/Pattern.qll

@@ -2,6 +2,7 @@ import codeql_ruby.AST
 private import codeql_ruby.Generated
 private import codeql.Locations
 private import internal.Pattern
+private import internal.Variable
 private import Variable
 
 /** A pattern. */
@@ -16,8 +17,8 @@ class VariablePattern extends Pattern {
   /** Gets the name of the variable used in this pattern. */
   final string getVariableName() { result = generated.getValue() }
 
-  /** Gets the variable used in this pattern. */
-  Variable getVariable() { this = result.getAnAccess() }
+  /** Gets the variable used in (or introduced by) this pattern. */
+  Variable getVariable() { access(this, result) }
 
   override string toString() { result = this.getVariableName() }
 }

ql/src/codeql_ruby/ast/Variable.qll

@@ -60,7 +60,11 @@ class VariableAccess extends AstNode, @token_identifier {
   override Generated::Identifier generated;
   Variable variable;
 
-  VariableAccess() { access(this, variable) }
+  VariableAccess() {
+    access(this, variable) and
+    // Do not generate an access at the defining location
+    not variable = TLocalVariable(_, _, this)
+  }
 
   /** Gets the variable this identifier refers to. */
   Variable getVariable() { result = variable }

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

@@ -123,11 +123,7 @@ private module Cached {
 
   cached
   predicate access(Generated::Identifier access, Variable variable) {
-    exists(string name |
-      name = access.getValue() and
-      // Do not generate an access at the defining location
-      not variable = TLocalVariable(_, name, access)
-    |
+    exists(string name | name = access.getValue() |
       variable = enclosingScope(access).getVariable(name) and
       not strictlyBefore(access.getLocation(), variable.getLocation())
       or

ql/test/library-tests/ast/params/params.expected

@@ -108,7 +108,7 @@ paramsInLambdas
 | params.rb:70:31:70:64 | -> { ... } | 0 | params.rb:70:35:70:35 | a | SimpleParameter |
 | params.rb:70:31:70:64 | -> { ... } | 1 | params.rb:70:38:70:45 | b | OptionalParameter |
 | params.rb:70:31:70:64 | -> { ... } | 2 | params.rb:70:48:70:53 | c | OptionalParameter |
-#select
+params
 | params.rb:4:30:4:32 | foo | 0 | SimpleParameter |
 | params.rb:4:35:4:37 | bar | 1 | SimpleParameter |
 | params.rb:4:40:4:42 | baz | 2 | SimpleParameter |

ql/test/library-tests/ast/params/params.ql

@@ -42,5 +42,7 @@ query predicate paramsInLambdas(Lambda l, int i, Parameter p, string pClass) {
 
 ////////////////////////////////////////////////////////////////////////////////
 // General query selecting all parameters
-from Parameter p
-select p, p.getPosition(), p.describeQlClass()
+query predicate params(Parameter p, int i, string pClass) {
+  i = p.getPosition() and
+  pClass = p.describeQlClass()
+}

ql/test/library-tests/variables/parameter.expected

@@ -1,6 +1,8 @@
-parameter
+parameterVariable
 | nested_scopes.rb:15:23:15:23 | a | nested_scopes.rb:15:23:15:23 | a |
+| nested_scopes.rb:16:26:16:26 | x | nested_scopes.rb:16:26:16:26 | x |
 | nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:16:29:16:29 | a |
+| nested_scopes.rb:18:26:18:26 | x | nested_scopes.rb:18:26:18:26 | x |
 | nested_scopes.rb:22:21:22:21 | a | nested_scopes.rb:22:21:22:21 | a |
 | parameters.rb:1:14:1:14 | x | parameters.rb:1:14:1:14 | x |
 | parameters.rb:1:18:1:18 | y | parameters.rb:1:18:1:18 | y |
@@ -18,10 +20,43 @@ parameter
 | parameters.rb:35:11:35:21 | a | parameters.rb:35:11:35:11 | a |
 | parameters.rb:40:12:40:19 | d | parameters.rb:40:12:40:12 | d |
 | parameters.rb:45:20:45:20 | _ | parameters.rb:45:20:45:20 | _ |
+| parameters.rb:49:12:49:16 | (..., ...) | parameters.rb:49:13:49:13 | a |
+| parameters.rb:49:12:49:16 | (..., ...) | parameters.rb:49:15:49:15 | b |
 | parameters.rb:54:14:54:24 | y | parameters.rb:54:14:54:14 | y |
-parameterNoAcess
-| nested_scopes.rb:16:26:16:26 | x |
-| nested_scopes.rb:18:26:18:26 | x |
-| parameters.rb:45:22:45:22 | _ |
-| scopes.rb:2:14:2:14 | x |
-| scopes.rb:9:14:9:14 | x |
+| scopes.rb:2:14:2:14 | x | scopes.rb:2:14:2:14 | x |
+| scopes.rb:9:14:9:14 | x | scopes.rb:9:14:9:14 | x |
+parameterVariableAccess
+| nested_scopes.rb:15:23:15:23 | a | nested_scopes.rb:15:23:15:23 | a | nested_scopes.rb:16:13:16:13 | a |
+| nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:17:15:17:15 | a |
+| nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:18:15:18:15 | a |
+| nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:16:29:16:29 | a | nested_scopes.rb:18:34:18:34 | a |
+| nested_scopes.rb:22:21:22:21 | a | nested_scopes.rb:22:21:22:21 | a | nested_scopes.rb:23:16:23:16 | a |
+| parameters.rb:1:14:1:14 | x | parameters.rb:1:14:1:14 | x | parameters.rb:3:9:3:9 | x |
+| parameters.rb:1:18:1:18 | y | parameters.rb:1:18:1:18 | y | parameters.rb:2:4:2:4 | y |
+| parameters.rb:1:18:1:18 | y | parameters.rb:1:18:1:18 | y | parameters.rb:4:9:4:9 | y |
+| parameters.rb:7:17:7:22 | client | parameters.rb:7:17:7:22 | client | parameters.rb:9:25:9:30 | client |
+| parameters.rb:7:17:7:22 | client | parameters.rb:7:17:7:22 | client | parameters.rb:11:41:11:46 | client |
+| parameters.rb:7:25:7:31 | *pizzas | parameters.rb:7:26:7:31 | pizzas | parameters.rb:8:6:8:11 | pizzas |
+| parameters.rb:7:25:7:31 | *pizzas | parameters.rb:7:26:7:31 | pizzas | parameters.rb:11:14:11:19 | pizzas |
+| parameters.rb:15:15:15:19 | **map | parameters.rb:15:17:15:19 | map | parameters.rb:16:3:16:5 | map |
+| parameters.rb:16:16:16:18 | key | parameters.rb:16:16:16:18 | key | parameters.rb:17:13:17:15 | key |
+| parameters.rb:16:21:16:25 | value | parameters.rb:16:21:16:25 | value | parameters.rb:17:22:17:26 | value |
+| parameters.rb:21:16:21:21 | &block | parameters.rb:21:17:21:21 | block | parameters.rb:22:3:22:7 | block |
+| parameters.rb:25:15:25:30 | name | parameters.rb:25:15:25:18 | name | parameters.rb:25:40:25:43 | name |
+| parameters.rb:25:15:25:30 | name | parameters.rb:25:15:25:18 | name | parameters.rb:26:8:26:11 | name |
+| parameters.rb:25:33:25:50 | size | parameters.rb:25:33:25:36 | size | parameters.rb:27:8:27:11 | size |
+| parameters.rb:30:15:30:20 | first | parameters.rb:30:15:30:19 | first | parameters.rb:31:11:31:15 | first |
+| parameters.rb:30:24:30:33 | middle | parameters.rb:30:24:30:29 | middle | parameters.rb:31:20:31:25 | middle |
+| parameters.rb:30:36:30:40 | last | parameters.rb:30:36:30:39 | last | parameters.rb:31:30:31:33 | last |
+| parameters.rb:35:11:35:21 | a | parameters.rb:35:11:35:11 | a | parameters.rb:37:11:37:11 | a |
+| parameters.rb:40:12:40:19 | d | parameters.rb:40:12:40:12 | d | parameters.rb:42:11:42:11 | d |
+| parameters.rb:45:20:45:20 | _ | parameters.rb:45:20:45:20 | _ | parameters.rb:45:22:45:22 | _ |
+| parameters.rb:45:20:45:20 | _ | parameters.rb:45:20:45:20 | _ | parameters.rb:46:8:46:8 | _ |
+| parameters.rb:49:12:49:16 | (..., ...) | parameters.rb:49:13:49:13 | a | parameters.rb:50:11:50:11 | a |
+| parameters.rb:49:12:49:16 | (..., ...) | parameters.rb:49:15:49:15 | b | parameters.rb:50:16:50:16 | b |
+| parameters.rb:54:14:54:24 | y | parameters.rb:54:14:54:14 | y | parameters.rb:56:9:56:9 | y |
+parameterVariableNoAcess
+| nested_scopes.rb:16:26:16:26 | x | nested_scopes.rb:16:26:16:26 | x |
+| nested_scopes.rb:18:26:18:26 | x | nested_scopes.rb:18:26:18:26 | x |
+| scopes.rb:2:14:2:14 | x | scopes.rb:2:14:2:14 | x |
+| scopes.rb:9:14:9:14 | x | scopes.rb:9:14:9:14 | x |

ql/test/library-tests/variables/parameter.ql

@@ -1,5 +1,12 @@
 import codeql_ruby.ast.Variable
 
-query predicate parameter(NamedParameter p, Variable v) { p.getAnAccess().getVariable() = v }
+query predicate parameterVariable(Parameter p, Variable v) { v = p.getAVariable() }
 
-query predicate parameterNoAcess(NamedParameter p) { not exists(p.getAnAccess()) }
+query predicate parameterVariableAccess(Parameter p, Variable v, VariableAccess va) {
+  v = p.getAVariable() and
+  va = v.getAnAccess()
+}
+
+query predicate parameterVariableNoAcess(Parameter p, Variable v) {
+  v = p.getAVariable() and not exists(v.getAnAccess())
+}