Initial work on user-facing AST library

.github/workflows/build.yml

@@ -46,8 +46,8 @@ jobs:
       - uses: actions/upload-artifact@v2
         if: ${{ matrix.os == 'ubuntu-latest' }}
         with:
-          name: ruby_ast.qll
-          path: ql/src/codeql_ruby/ast.qll
+          name: Generated.qll
+          path: ql/src/codeql_ruby/Generated.qll
       - uses: actions/upload-artifact@v2
         with:
           name: extractor-${{ matrix.os }}

Cargo.lock

@@ -64,9 +64,9 @@ checksum = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 
 [[package]]
 name = "cc"
-version = "1.0.62"
+version = "1.0.65"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1770ced377336a88a67c473594ccc14eca6f4559217c34f64aac8f83d641b40"
+checksum = "95752358c8f7552394baf48cd82695b345628ad3f170d607de3ca03b8dacca15"
 
 [[package]]
 name = "cfg-if"
@@ -397,9 +397,9 @@ dependencies = [
 
 [[package]]
 name = "smallvec"
-version = "1.4.2"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fbee7696b84bbf3d89a1c2eccff0850e3047ed46bfcd2e92c29a2d074d57e252"
+checksum = "7acad6f34eb9e8a259d3283d1e8c1d34d7415943d4895f65cc73813c7396fc85"
 
 [[package]]
 name = "strsim"
@@ -409,9 +409,9 @@ checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
 [[package]]
 name = "syn"
-version = "1.0.48"
+version = "1.0.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc371affeffc477f42a221a1e4297aedcea33d47d19b61455588bd9d8f6b19ac"
+checksum = "443b4178719c5a851e1bde36ce12da21d74a0e60b4d982ec3385a933c812f0f6"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -535,7 +535,7 @@ dependencies = [
 [[package]]
 name = "tree-sitter-ruby"
 version = "0.17.0"
-source = "git+https://github.com/tree-sitter/tree-sitter-ruby.git?rev=93632008c63e0577413bbedf120fb92a96397785#93632008c63e0577413bbedf120fb92a96397785"
+source = "git+https://github.com/nickrolfe/tree-sitter-ruby.git?branch=refinements#cf76d2c60dac54259912f0c3c4d5c73e78304ace"
 dependencies = [
  "cc",
  "tree-sitter",

README.md

@@ -12,13 +12,13 @@ cargo build --release
 
 ## Generating the database schema and QL library
 
-The generated `ql/src/ruby.dbscheme` and `ql/src/codeql_ruby/ast.qll` files are included in the repository, but they can be re-generated as follows:
+The generated `ql/src/ruby.dbscheme` and `ql/src/codeql_ruby/Generated.qll` files are included in the repository, but they can be re-generated as follows:
 
 ```bash
 # Run the generator
 cargo run --release -p ruby-generator
 # Then auto-format the QL library
-codeql query format -i ql/src/codeql_ruby/ast.qll
+codeql query format -i ql/src/codeql_ruby/Generated.qll
 ```
 
 ## Building a CodeQL database for a Ruby program

create-extractor-pack.ps1

@@ -1,7 +1,7 @@
 cargo build --release
 
 cargo run --release -p ruby-generator
-codeql query format -i ql\src\codeql_ruby\ast.qll
+codeql query format -i ql\src\codeql_ruby\Generated.qll
 
 rm -Recurse -Force extractor-pack
 mkdir extractor-pack | Out-Null

create-extractor-pack.sh

@@ -13,7 +13,7 @@ fi
 cargo build --release
 
 cargo run --release -p ruby-generator
-codeql query format -i ql/src/codeql_ruby/ast.qll
+codeql query format -i ql/src/codeql_ruby/Generated.qll
 
 rm -rf extractor-pack
 mkdir -p extractor-pack

extractor/Cargo.toml

@@ -10,7 +10,7 @@ edition = "2018"
 flate2 = "1.0"
 node-types = { path = "../node-types" }
 tree-sitter = "0.17"
-tree-sitter-ruby = { git = "https://github.com/tree-sitter/tree-sitter-ruby.git", rev = "93632008c63e0577413bbedf120fb92a96397785" }
+tree-sitter-ruby = { git = "https://github.com/nickrolfe/tree-sitter-ruby.git", branch = "refinements" }
 clap = "2.33"
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["env-filter"] }

generator/Cargo.toml

@@ -10,4 +10,4 @@ edition = "2018"
 node-types = { path = "../node-types" }
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["env-filter"] }
-tree-sitter-ruby = { git = "https://github.com/tree-sitter/tree-sitter-ruby.git", rev = "93632008c63e0577413bbedf120fb92a96397785" }
+tree-sitter-ruby = { git = "https://github.com/nickrolfe/tree-sitter-ruby.git", branch = "refinements" }

generator/src/main.rs

@@ -574,7 +574,7 @@ fn main() {
         name: "Ruby".to_owned(),
         node_types: tree_sitter_ruby::NODE_TYPES,
         dbscheme_path: PathBuf::from("ql/src/ruby.dbscheme"),
-        ql_library_path: PathBuf::from("ql/src/codeql_ruby/ast.qll"),
+        ql_library_path: PathBuf::from("ql/src/codeql_ruby/Generated.qll"),
     };
     match node_types::read_node_types_str(&ruby.node_types) {
         Err(e) => {

generator/src/ql.rs

@@ -214,10 +214,12 @@ pub fn write<'a>(
         " * Automatically generated from the tree-sitter grammar; do not edit\n"
     )?;
     write!(file, " */\n\n")?;
+    write!(file, "module Generated {{\n")?;
 
     for element in elements {
         write!(file, "{}\n\n", &element)?;
     }
 
+    write!(file, "}}")?;
     Ok(())
 }

ql/src/codeql_ruby/AST.qll

@@ -0,0 +1,40 @@
+import codeql_ruby.Method
+import codeql_ruby.Parameter
+private import codeql_ruby.Generated
+
+class Location = Generated::Location;
+
+/**
+ * A node in the abstract syntax tree. This class is the base class for all Ruby
+ * program elements.
+ */
+class AstNode extends @ast_node {
+  /**
+   * Gets the name of a primary CodeQL class to which this node belongs.
+   *
+   * This predicate always has a result. If no primary class can be
+   * determined, the result is `"???"`. If multiple primary classes match,
+   * this predicate can have multiple results.
+   */
+  string describeQlClass() { result = "???" }
+
+  /** Gets a textual representation of this node. */
+  string toString() { result = "AstNode" }
+
+  /** Gets the location if this node. */
+  Location getLocation() { result = this.(Generated::AstNode).getLocation() }
+}
+
+/**
+ * Models program elements for destructured patterns.
+ */
+abstract class Pattern extends AstNode {
+  /** Gets the number of elements in this pattern. */
+  abstract int getNumberOfElements();
+
+  /** Gets the nth element in this pattern. */
+  abstract AstNode getElement(int n);
+
+  /** Gets an element in this pattern. */
+  AstNode getAnElement() { result = this.getElement(_) }
+}

ql/src/codeql_ruby/Method.qll

@@ -0,0 +1,119 @@
+import codeql_ruby.AST
+private import codeql_ruby.Generated
+
+/** A Ruby method. */
+class Method extends @method, AstNode {
+  Generated::Method generated;
+
+  Method() { generated = this }
+
+  override string describeQlClass() { result = "Method" }
+
+  override string toString() { result = this.getName() }
+
+  /** Gets the name of the method. */
+  string getName() {
+    result = generated.getName().(Generated::Token).getValue() or
+    // TODO: use hand-written Symbol class
+    result = generated.getName().(Generated::Symbol).toString() or
+    result = generated.getName().(Generated::Setter).getName().getValue() + "="
+  }
+
+  /**
+   * Holds if this is a setter method, as in the following example:
+   * ```
+   * class Person
+   *   def name=(n)
+   *     @name = n
+   *   end
+   * end
+   * ```
+   */
+  predicate isSetter() { generated.getName() instanceof Generated::Setter }
+
+  /** Gets the number of parameters of this method. */
+  int getNumberOfParameters() { result = count(this.getAParameter()) }
+
+  /** Gets a parameter of this method. */
+  Parameter getAParameter() { result = this.getParameter(_) }
+
+  /** Gets the nth parameter of this method. */
+  Parameter getParameter(int n) { result = generated.getParameters().getChild(n) }
+}
+
+/**
+ * A Ruby lambda (anonymous method). For example:
+ * ```
+ * -> (x) { x + 1 }
+ * ```
+ */
+class Lambda extends @lambda, AstNode {
+  Generated::Lambda generated;
+
+  Lambda() { generated = this }
+
+  override string describeQlClass() { result = "Lambda" }
+
+  override string toString() { result = "-> { ... }" }
+
+  /** Gets the number of parameters of this lambda. */
+  int getNumberOfParameters() { result = count(this.getAParameter()) }
+
+  /** Gets a parameter of this lambda. */
+  Parameter getAParameter() { result = this.getParameter(_) }
+
+  /** Gets the nth parameter of this lambda. */
+  Parameter getParameter(int n) { result = generated.getParameters().getChild(n) }
+}
+
+/** A Ruby block. */
+abstract class Block extends AstNode {
+  /** Gets the number of parameters of this block. */
+  abstract int getNumberOfParameters();
+
+  /** Gets the nth parameter of this block. */
+  abstract Parameter getParameter(int n);
+
+  /** Gets a parameter of this block. */
+  Parameter getAParameter() { result = this.getParameter(_) }
+  // TODO: body/statements
+}
+
+/** A Ruby block enclosed within `do` and `end`. */
+class DoBlock extends @do_block, Block {
+  Generated::DoBlock generated;
+
+  DoBlock() { generated = this }
+
+  override string describeQlClass() { result = "DoBlock" }
+
+  override string toString() { result = "| ... |" }
+
+  /** Gets the number of parameters of this block. */
+  override int getNumberOfParameters() { result = count(this.getAParameter()) }
+
+  /** Gets the nth parameter of this block. */
+  override Parameter getParameter(int n) { result = generated.getParameters().getChild(n) }
+}
+
+/**
+ * A Ruby block defined using curly braces, e.g. in the following code:
+ * ```
+ * names.each { |name| puts name }
+ * ```
+ */
+class BraceBlock extends @block, Block {
+  Generated::Block generated;
+
+  BraceBlock() { generated = this }
+
+  override string describeQlClass() { result = "BraceBlock" }
+
+  override string toString() { result = "{ ... }" }
+
+  /** Gets the number of parameters of this block. */
+  override int getNumberOfParameters() { result = count(this.getAParameter()) }
+
+  /** Gets the nth parameter of this block. */
+  override Parameter getParameter(int n) { result = generated.getParameters().getChild(n) }
+}

ql/src/codeql_ruby/Parameter.qll

@@ -0,0 +1,182 @@
+import codeql_ruby.AST
+private import codeql_ruby.Generated
+
+/**
+ * A parameter to a block, lambda, or method.
+ */
+abstract class Parameter extends AstNode {
+  /**
+   * Gets the position of this parameter in the parent block, lambda, or
+   * method's parameter list.
+   */
+  int getPosition() {
+    exists(Method m | m.getParameter(result) = this) or
+    exists(Block b | b.getParameter(result) = this) or
+    exists(Lambda l | l.getParameter(result) = this)
+  }
+}
+
+/**
+ * A parameter that is a block. For example, `&bar` in the following code:
+ * ```
+ * def foo(&bar)
+ *   bar.call if block_given?
+ * end
+ * ```
+ */
+class BlockParameter extends @block_parameter, Parameter {
+  Generated::BlockParameter generated;
+
+  BlockParameter() { generated = this }
+
+  override string describeQlClass() { result = "BlockParameter" }
+
+  override string toString() { result = "&" + this.getName() }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = generated.getName().getValue() }
+}
+
+/**
+ * A parameter that is destructured. For example, the parameter `(a, b)` in the
+ * following code:
+ * ```
+ * pairs.each do |(a, b)|
+ *   puts a + b
+ * end
+ * ```
+ */
+class PatternParameter extends @destructured_parameter, Parameter, Pattern {
+  Generated::DestructuredParameter generated;
+
+  PatternParameter() { generated = this }
+
+  override string describeQlClass() { result = "PatternParameter" }
+
+  override string toString() { result = "(..., ...)" }
+
+  /**
+   * Gets the number of parameters of this destructuring.
+   */
+  override int getNumberOfElements() { result = count(this.getElement(_)) }
+
+  /**
+   * Gets the nth parameter of this pattern.
+   */
+  override AstNode getElement(int n) { result = generated.getChild(n) }
+}
+
+/**
+ * A hash-splat (or double-splat) parameter. For example, `**options` in the
+ * following code:
+ * ```
+ * def foo(bar, **options)
+ *   ...
+ * end
+ * ```
+ */
+class HashSplatParameter extends @hash_splat_parameter, Parameter {
+  Generated::HashSplatParameter generated;
+
+  HashSplatParameter() { generated = this }
+
+  override string describeQlClass() { result = "HashSplatParameter" }
+
+  override string toString() { result = "**" + this.getName() }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = generated.getName().getValue() }
+}
+
+/**
+ * TODO
+ */
+class KeywordParameter extends @keyword_parameter, Parameter {
+  Generated::KeywordParameter generated;
+
+  KeywordParameter() { generated = this }
+
+  override string describeQlClass() { result = "KeywordParameter" }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = generated.getName().getValue() }
+
+  /**
+   * Gets the default value, i.e. the value assigned to the parameter when one
+   * is not provided by the caller. If the parameter is mandatory and does not
+   * have a default value, this predicate has no result.
+   * TODO: better return type (Expr?)
+   */
+  AstNode getDefaultValue() { result = generated.getValue() }
+
+  override string toString() { result = this.getName() }
+}
+
+/**
+ * An optional parameter. For example, the parameter `name` in the following
+ * code:
+ * ```
+ * def say_hello(name = 'Anon')
+ *   puts "hello #{name}"
+ * end
+ * ```
+ */
+class OptionalParameter extends @optional_parameter, Parameter {
+  Generated::OptionalParameter generated;
+
+  OptionalParameter() { generated = this }
+
+  override string describeQlClass() { result = "OptionalParameter" }
+
+  override string toString() { result = this.getName() }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = generated.getName().getValue() }
+
+  /**
+   * Gets the default value, i.e. the value assigned to the parameter when one
+   * is not provided by the caller.
+   * TODO: better return type (Expr?)
+   */
+  AstNode getDefaultValue() { result = generated.getValue() }
+}
+
+/**
+ * A splat parameter. For example, `*values` in the following code:
+ * ```
+ * def foo(bar, *values)
+ *   ...
+ * end
+ * ```
+ */
+class SplatParameter extends @splat_parameter, Parameter {
+  Generated::SplatParameter generated;
+
+  SplatParameter() { generated = this }
+
+  override string describeQlClass() { result = "SplatParameter" }
+
+  override string toString() { result = this.getName() }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = generated.getName().getValue() }
+}
+
+/**
+ * An identifier that is a parameter in a block, lambda, or method.
+ */
+class IdentifierParameter extends @token_identifier, Parameter {
+  IdentifierParameter() {
+    block_parameters_child(_, _, this) or
+    destructured_parameter_child(_, _, this) or
+    lambda_parameters_child(_, _, this) or
+    method_parameters_child(_, _, this)
+  }
+
+  override string describeQlClass() { result = "IdentifierParameter" }
+
+  override string toString() { result = this.getName() }
+
+  /** Gets the name of the parameter. */
+  string getName() { result = this.(Generated::Identifier).getValue() }
+}

ql/src/codeql_ruby/controlflow/BasicBlocks.qll

@@ -1,6 +1,6 @@
 /** Provides classes representing basic blocks. */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import codeql_ruby.controlflow.ControlFlowGraph
 private import internal.ControlFlowGraphImpl
 private import SuccessorTypes

ql/src/codeql_ruby/controlflow/ControlFlowGraph.qll

@@ -1,6 +1,6 @@
 /** Provides classes representing the control flow graph. */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import codeql_ruby.controlflow.BasicBlocks
 private import SuccessorTypes
 private import internal.ControlFlowGraphImpl

ql/src/codeql_ruby/controlflow/internal/AstNodes.qll

@@ -3,7 +3,7 @@
  * will likely be part of the hand-written user-facing AST layer.
  */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 
 class LogicalNotAstNode extends Unary {
   AstNode operand;

ql/src/codeql_ruby/controlflow/internal/Completion.qll

@@ -4,7 +4,7 @@
  * A completion represents how a statement or expression terminates.
  */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import codeql_ruby.controlflow.ControlFlowGraph
 private import AstNodes
 private import NonReturning

ql/src/codeql_ruby/controlflow/internal/Consistency.qll

@@ -1,4 +1,4 @@
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import codeql_ruby.controlflow.ControlFlowGraph
 private import Completion
 private import Splitting

ql/src/codeql_ruby/controlflow/internal/ControlFlowGraphImpl.qll

@@ -31,7 +31,7 @@
  * caught up by its surrounding loop and turned into a `NormalCompletion`.
  */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import AstNodes
 private import codeql_ruby.controlflow.ControlFlowGraph
 private import Completion

ql/src/codeql_ruby/controlflow/internal/NonReturning.qll

@@ -1,6 +1,6 @@
 /** Provides a simple analysis for identifying calls that will not return. */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import Completion
 
 /** A call that definitely does not return (conservative analysis). */

ql/src/codeql_ruby/controlflow/internal/Splitting.qll

@@ -2,7 +2,7 @@
  * Provides classes and predicates relevant for splitting the control flow graph.
  */
 
-private import codeql_ruby.ast
+private import codeql_ruby.Generated::Generated
 private import AstNodes
 private import Completion
 private import ControlFlowGraphImpl

ql/src/codeql_ruby/printAst.qll

@@ -6,7 +6,7 @@
  * to hold for only the AST nodes you wish to view.
  */
 
-import codeql_ruby.ast
+import codeql_ruby.Generated
 
 /**
  * The query can extend this class to control which nodes are printed.
@@ -17,13 +17,13 @@ class PrintAstConfiguration extends string {
   /**
    * Holds if the given node should be printed.
    */
-  predicate shouldPrintNode(AstNode n) { any() }
+  predicate shouldPrintNode(Generated::AstNode n) { any() }
 }
 
 /**
  * A node in the output tree.
  */
-class PrintAstNode extends AstNode {
+class PrintAstNode extends Generated::AstNode {
   string getProperty(string key) {
     key = "semmle.label" and
     result = "[" + this.describeQlClass() + "] " + this.toString()
@@ -36,15 +36,15 @@ class PrintAstNode extends AstNode {
    */
   predicate shouldPrint() {
     (
-      not this instanceof Token
+      not this instanceof Generated::Token
       or
-      exists(AstNode parent | parent.getAFieldOrChild() = this)
+      exists(Generated::AstNode parent | parent.getAFieldOrChild() = this)
     ) and
     shouldPrintNode(this)
   }
 }
 
-private predicate shouldPrintNode(AstNode n) {
+private predicate shouldPrintNode(Generated::AstNode n) {
   exists(PrintAstConfiguration config | config.shouldPrintNode(n))
 }
 

ql/src/printAst.ql

@@ -8,6 +8,7 @@
  */
 
 import codeql_ruby.printAst
+import codeql.files.FileSystem
 
 /**
  * The source file to generate an AST from.
@@ -36,7 +37,7 @@ File getFileBySourceArchiveName(string name) {
  * Overrides the configuration to print only nodes in the selected source file.
  */
 class Cfg extends PrintAstConfiguration {
-  override predicate shouldPrintNode(AstNode n) {
+  override predicate shouldPrintNode(Generated::AstNode n) {
     n.getLocation().getFile() = getFileBySourceArchiveName(selectedSourceFile())
   }
 }

ql/src/ruby.dbscheme

@@ -201,7 +201,12 @@ binary_def(
   int loc: @location ref
 );
 
-@block_child_type = @block_parameters | @token_empty_statement | @underscore_statement
+block_parameters(
+  unique int block: @block ref,
+  unique int block_parameters: @block_parameters ref
+);
+
+@block_child_type = @token_empty_statement | @underscore_statement
 
 #keyset[block, index]
 block_child(
@@ -399,7 +404,12 @@ do_def(
   int loc: @location ref
 );
 
-@do_block_child_type = @block_parameters | @else | @ensure | @rescue | @token_empty_statement | @underscore_statement
+do_block_parameters(
+  unique int do_block: @do_block ref,
+  unique int block_parameters: @block_parameters ref
+);
+
+@do_block_child_type = @else | @ensure | @rescue | @token_empty_statement | @underscore_statement
 
 #keyset[do_block, index]
 do_block_child(
@@ -1063,7 +1073,7 @@ setter_def(
   unique int id: @setter,
   int parent: @ast_node_parent ref,
   int parent_index: int ref,
-  int child: @token_identifier ref,
+  int name: @token_identifier ref,
   int loc: @location ref
 );
 

ql/src/ruby.qll

@@ -0,0 +1 @@
+import codeql_ruby.AST

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

@@ -0,0 +1,139 @@
+idParams
+| params.rb:4:30:4:32 | foo | foo |
+| params.rb:4:35:4:37 | bar | bar |
+| params.rb:4:40:4:42 | baz | baz |
+| params.rb:9:15:9:17 | key | key |
+| params.rb:9:20:9:24 | value | value |
+| params.rb:14:11:14:13 | foo | foo |
+| params.rb:14:16:14:18 | bar | bar |
+| params.rb:17:32:17:32 | a | a |
+| params.rb:17:35:17:35 | b | b |
+| params.rb:17:38:17:38 | c | c |
+| params.rb:22:16:22:16 | a | a |
+| params.rb:22:19:22:19 | b | b |
+| params.rb:25:24:25:28 | first | first |
+| params.rb:25:31:25:36 | second | second |
+| params.rb:25:41:25:45 | third | third |
+| params.rb:25:48:25:53 | fourth | fourth |
+| params.rb:30:23:30:28 | wibble | wibble |
+| params.rb:34:16:34:18 | val | val |
+| params.rb:38:26:38:26 | x | x |
+| params.rb:41:32:41:32 | x | x |
+| params.rb:53:34:53:34 | x | x |
+| params.rb:58:33:58:36 | val1 | val1 |
+| params.rb:65:29:65:32 | name | name |
+| params.rb:70:35:70:35 | a | a |
+blockParams
+| params.rb:46:28:46:33 | &block | block |
+| params.rb:62:29:62:34 | &block | block |
+patternParams
+| params.rb:17:31:17:39 | (..., ...) | params.rb:17:32:17:32 | a | 0 |
+| params.rb:17:31:17:39 | (..., ...) | params.rb:17:35:17:35 | b | 1 |
+| params.rb:17:31:17:39 | (..., ...) | params.rb:17:38:17:38 | c | 2 |
+| params.rb:22:15:22:20 | (..., ...) | params.rb:22:16:22:16 | a | 0 |
+| params.rb:22:15:22:20 | (..., ...) | params.rb:22:19:22:19 | b | 1 |
+| params.rb:25:23:25:37 | (..., ...) | params.rb:25:24:25:28 | first | 0 |
+| params.rb:25:23:25:37 | (..., ...) | params.rb:25:31:25:36 | second | 1 |
+| params.rb:25:40:25:54 | (..., ...) | params.rb:25:41:25:45 | third | 0 |
+| params.rb:25:40:25:54 | (..., ...) | params.rb:25:48:25:53 | fourth | 1 |
+splatParams
+| params.rb:30:31:30:36 | splat | splat |
+| params.rb:34:21:34:26 | splat | splat |
+| params.rb:38:29:38:33 | blah | blah |
+hashSplatParams
+| params.rb:30:39:30:52 | **double_splat | double_splat |
+| params.rb:34:29:34:42 | **double_splat | double_splat |
+| params.rb:38:36:38:43 | **wibble | wibble |
+keywordParams
+| params.rb:41:35:41:38 | foo | foo | (none) |
+| params.rb:41:41:41:46 | bar | bar | AstNode |
+| params.rb:49:28:49:30 | xx | xx | (none) |
+| params.rb:49:33:49:39 | yy | yy | AstNode |
+| params.rb:53:37:53:38 | y | y | (none) |
+| params.rb:53:41:53:44 | z | z | AstNode |
+optionalParams
+| params.rb:58:39:58:46 | val2 | val2 | params.rb:58:46:58:46 | AstNode |
+| params.rb:58:49:58:58 | val3 | val3 | params.rb:58:56:58:58 | AstNode |
+| params.rb:65:35:65:42 | age | age | params.rb:65:41:65:42 | AstNode |
+| params.rb:70:38:70:45 | b | b | params.rb:70:42:70:45 | AstNode |
+| params.rb:70:48:70:53 | c | c | params.rb:70:52:70:53 | AstNode |
+paramsInMethods
+| params.rb:4:1:5:3 | identifier_method_params | 0 | params.rb:4:30:4:32 | foo | IdentifierParameter |
+| params.rb:4:1:5:3 | identifier_method_params | 1 | params.rb:4:35:4:37 | bar | IdentifierParameter |
+| params.rb:4:1:5:3 | identifier_method_params | 2 | params.rb:4:40:4:42 | baz | IdentifierParameter |
+| params.rb:17:1:18:3 | destructured_method_param | 0 | params.rb:17:31:17:39 | (..., ...) | PatternParameter |
+| params.rb:30:1:31:3 | method_with_splat | 0 | params.rb:30:23:30:28 | wibble | IdentifierParameter |
+| params.rb:30:1:31:3 | method_with_splat | 1 | params.rb:30:31:30:36 | splat | SplatParameter |
+| params.rb:30:1:31:3 | method_with_splat | 2 | params.rb:30:39:30:52 | **double_splat | HashSplatParameter |
+| params.rb:41:1:43:3 | method_with_keyword_params | 0 | params.rb:41:32:41:32 | x | IdentifierParameter |
+| params.rb:41:1:43:3 | method_with_keyword_params | 1 | params.rb:41:35:41:38 | foo | KeywordParameter |
+| params.rb:41:1:43:3 | method_with_keyword_params | 2 | params.rb:41:41:41:46 | bar | KeywordParameter |
+| params.rb:46:1:48:3 | use_block_with_keyword | 0 | params.rb:46:28:46:33 | &block | BlockParameter |
+| params.rb:58:1:59:3 | method_with_optional_params | 0 | params.rb:58:33:58:36 | val1 | IdentifierParameter |
+| params.rb:58:1:59:3 | method_with_optional_params | 1 | params.rb:58:39:58:46 | val2 | OptionalParameter |
+| params.rb:58:1:59:3 | method_with_optional_params | 2 | params.rb:58:49:58:58 | val3 | OptionalParameter |
+| params.rb:62:1:64:3 | use_block_with_optional | 0 | params.rb:62:29:62:34 | &block | BlockParameter |
+paramsInBlocks
+| params.rb:9:11:11:3 | \| ... \| | 0 | params.rb:9:15:9:17 | key | IdentifierParameter |
+| params.rb:9:11:11:3 | \| ... \| | 1 | params.rb:9:20:9:24 | value | IdentifierParameter |
+| params.rb:22:12:22:32 | { ... } | 0 | params.rb:22:15:22:20 | (..., ...) | PatternParameter |
+| params.rb:34:12:35:3 | \| ... \| | 0 | params.rb:34:16:34:18 | val | IdentifierParameter |
+| params.rb:34:12:35:3 | \| ... \| | 1 | params.rb:34:21:34:26 | splat | SplatParameter |
+| params.rb:34:12:35:3 | \| ... \| | 2 | params.rb:34:29:34:42 | **double_splat | HashSplatParameter |
+| params.rb:49:24:51:3 | \| ... \| | 0 | params.rb:49:28:49:30 | xx | KeywordParameter |
+| params.rb:49:24:51:3 | \| ... \| | 1 | params.rb:49:33:49:39 | yy | KeywordParameter |
+| params.rb:65:25:67:3 | \| ... \| | 0 | params.rb:65:29:65:32 | name | IdentifierParameter |
+| params.rb:65:25:67:3 | \| ... \| | 1 | params.rb:65:35:65:42 | age | OptionalParameter |
+paramsInLambdas
+| params.rb:14:7:14:33 | -> { ... } | 0 | params.rb:14:11:14:13 | foo | IdentifierParameter |
+| params.rb:14:7:14:33 | -> { ... } | 1 | params.rb:14:16:14:18 | bar | IdentifierParameter |
+| params.rb:25:19:27:1 | -> { ... } | 0 | params.rb:25:23:25:37 | (..., ...) | PatternParameter |
+| params.rb:25:19:27:1 | -> { ... } | 1 | params.rb:25:40:25:54 | (..., ...) | PatternParameter |
+| params.rb:38:22:38:47 | -> { ... } | 0 | params.rb:38:26:38:26 | x | IdentifierParameter |
+| params.rb:38:22:38:47 | -> { ... } | 1 | params.rb:38:29:38:33 | blah | SplatParameter |
+| params.rb:38:22:38:47 | -> { ... } | 2 | params.rb:38:36:38:43 | **wibble | HashSplatParameter |
+| params.rb:53:30:55:1 | -> { ... } | 0 | params.rb:53:34:53:34 | x | IdentifierParameter |
+| params.rb:53:30:55:1 | -> { ... } | 1 | params.rb:53:37:53:38 | y | KeywordParameter |
+| params.rb:53:30:55:1 | -> { ... } | 2 | params.rb:53:41:53:44 | z | KeywordParameter |
+| params.rb:70:31:70:64 | -> { ... } | 0 | params.rb:70:35:70:35 | a | IdentifierParameter |
+| 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.rb:4:30:4:32 | foo | 0 | IdentifierParameter |
+| params.rb:4:35:4:37 | bar | 1 | IdentifierParameter |
+| params.rb:4:40:4:42 | baz | 2 | IdentifierParameter |
+| params.rb:9:15:9:17 | key | 0 | IdentifierParameter |
+| params.rb:9:20:9:24 | value | 1 | IdentifierParameter |
+| params.rb:14:11:14:13 | foo | 0 | IdentifierParameter |
+| params.rb:14:16:14:18 | bar | 1 | IdentifierParameter |
+| params.rb:17:31:17:39 | (..., ...) | 0 | PatternParameter |
+| params.rb:22:15:22:20 | (..., ...) | 0 | PatternParameter |
+| params.rb:25:23:25:37 | (..., ...) | 0 | PatternParameter |
+| params.rb:25:40:25:54 | (..., ...) | 1 | PatternParameter |
+| params.rb:30:23:30:28 | wibble | 0 | IdentifierParameter |
+| params.rb:30:31:30:36 | splat | 1 | SplatParameter |
+| params.rb:30:39:30:52 | **double_splat | 2 | HashSplatParameter |
+| params.rb:34:16:34:18 | val | 0 | IdentifierParameter |
+| params.rb:34:21:34:26 | splat | 1 | SplatParameter |
+| params.rb:34:29:34:42 | **double_splat | 2 | HashSplatParameter |
+| params.rb:38:26:38:26 | x | 0 | IdentifierParameter |
+| params.rb:38:29:38:33 | blah | 1 | SplatParameter |
+| params.rb:38:36:38:43 | **wibble | 2 | HashSplatParameter |
+| params.rb:41:32:41:32 | x | 0 | IdentifierParameter |
+| params.rb:41:35:41:38 | foo | 1 | KeywordParameter |
+| params.rb:41:41:41:46 | bar | 2 | KeywordParameter |
+| params.rb:46:28:46:33 | &block | 0 | BlockParameter |
+| params.rb:49:28:49:30 | xx | 0 | KeywordParameter |
+| params.rb:49:33:49:39 | yy | 1 | KeywordParameter |
+| params.rb:53:34:53:34 | x | 0 | IdentifierParameter |
+| params.rb:53:37:53:38 | y | 1 | KeywordParameter |
+| params.rb:53:41:53:44 | z | 2 | KeywordParameter |
+| params.rb:58:33:58:36 | val1 | 0 | IdentifierParameter |
+| params.rb:58:39:58:46 | val2 | 1 | OptionalParameter |
+| params.rb:58:49:58:58 | val3 | 2 | OptionalParameter |
+| params.rb:62:29:62:34 | &block | 0 | BlockParameter |
+| params.rb:65:29:65:32 | name | 0 | IdentifierParameter |
+| params.rb:65:35:65:42 | age | 1 | OptionalParameter |
+| params.rb:70:35:70:35 | a | 0 | IdentifierParameter |
+| params.rb:70:38:70:45 | b | 1 | OptionalParameter |
+| params.rb:70:48:70:53 | c | 2 | OptionalParameter |

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

@@ -0,0 +1,46 @@
+import ruby
+
+////////////////////////////////////////////////////////////////////////////////
+// Query predicates for various types of parameter
+query predicate idParams(IdentifierParameter ip, string name) { name = ip.getName() }
+
+query predicate blockParams(BlockParameter bp, string name) { name = bp.getName() }
+
+query predicate patternParams(PatternParameter pp, Parameter child, int childIndex) {
+  pp.getElement(childIndex) = child
+}
+
+query predicate splatParams(SplatParameter sp, string name) { name = sp.getName() }
+
+query predicate hashSplatParams(HashSplatParameter hsp, string name) { name = hsp.getName() }
+
+query predicate keywordParams(KeywordParameter kp, string name, string defaultValueStr) {
+  name = kp.getName() and
+  if exists(kp.getDefaultValue())
+  then defaultValueStr = kp.getDefaultValue().toString()
+  else defaultValueStr = "(none)"
+}
+
+query predicate optionalParams(OptionalParameter op, string name, AstNode defaultValue) {
+  name = op.getName() and
+  defaultValue = op.getDefaultValue()
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Query predicates for various contexts of parameters
+query predicate paramsInMethods(Method m, int i, Parameter p, string pClass) {
+  p = m.getParameter(i) and pClass = p.describeQlClass()
+}
+
+query predicate paramsInBlocks(Block b, int i, Parameter p, string pClass) {
+  p = b.getParameter(i) and pClass = p.describeQlClass()
+}
+
+query predicate paramsInLambdas(Lambda l, int i, Parameter p, string pClass) {
+  p = l.getParameter(i) and pClass = p.describeQlClass()
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// General query selecting all parameters
+from Parameter p
+select p, p.getPosition(), p.describeQlClass()

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

@@ -0,0 +1,70 @@
+# Tests for the different kinds and contexts of parameters.
+
+# Method containing identifier parameters
+def identifier_method_params(foo, bar, baz)
+end
+
+# Block containing identifier parameters
+hash = {}
+hash.each do |key, value|
+  puts "#{key} -> #{value}"
+end
+
+# Lambda containing identifier parameters
+sum = -> (foo, bar) { foo + bar }
+
+# Method containing destructured parameters
+def destructured_method_param((a, b, c))
+end
+
+# Block containing destructured parameters
+array = []
+array.each { |(a, b)| puts a+b }
+
+# Lambda containing destructured parameters
+sum_four_values = -> ((first, second), (third, fourth)) {
+  first + second + third + fourth
+}
+
+# Method containing splat and hash-splat params
+def method_with_splat(wibble, *splat, **double_splat)
+end
+
+# Block with splat and hash-splat parameter
+array.each do |val, *splat, **double_splat|
+end
+
+# Lambda with splat and hash-splat
+lambda_with_splats = -> (x, *blah, **wibble) {}
+
+# Method containing keyword parameters
+def method_with_keyword_params(x, foo:, bar: 7)
+  x + foo + bar
+end
+
+# Block with keyword parameters
+def use_block_with_keyword(&block)
+  puts(block.call bar: 2, foo: 3)
+end
+use_block_with_keyword do |xx:, yy: 100|
+  xx + yy
+end
+
+lambda_with_keyword_params = -> (x, y:, z: 3) {
+  x + y + z
+}
+
+# Method containing optional parameters
+def method_with_optional_params(val1, val2 = 0, val3 = 100)
+end
+
+# Block containing optional parameter
+def use_block_with_optional(&block)
+  block.call 'Zeus'
+end
+use_block_with_optional do |name, age = 99|
+  puts "#{name} is #{age} years old"
+end
+
+# Lambda containing optional parameters
+lambda_with_optional_params = -> (a, b = 1000, c = 20) { a+b+c }