Merge pull request #179 from smowton/smowton/feature/printast

Add barebones PrintAST for Go

Author: max-schaefer

ql/src/semmle/go/AST.qll

@@ -45,6 +45,12 @@ class AstNode extends @node, Locatable {
   /** Gets the innermost function definition to which this AST node belongs, if any. */
   FuncDef getEnclosingFunction() { result = getParent().parentInSameFunction*() }
 
+  /**
+   * Describes important CodeQL classes for this node. May
+   * return multiple values.
+   */
+  string describeQlClass() { result = "???" }
+
   override string toString() { result = "AST node" }
 }
 

ql/src/semmle/go/Comments.qll

@@ -27,6 +27,8 @@ class Comment extends @comment, AstNode {
   CommentGroup getGroup() { this = result.getAComment() }
 
   override string toString() { result = "comment" }
+
+  override string describeQlClass() { result = "Comment" }
 }
 
 /**
@@ -59,6 +61,8 @@ class CommentGroup extends @comment_group, AstNode {
   int getNumComment() { result = count(getAComment()) }
 
   override string toString() { result = "comment group" }
+
+  override string describeQlClass() { result = "CommentGroup" }
 }
 
 /**
@@ -109,6 +113,8 @@ class DocComment extends CommentGroup {
 
   /** Gets the program element documented by this comment group. */
   Documentable getDocumentedElement() { result = node }
+
+  override string describeQlClass() { result = "DocComment" }
 }
 
 /**
@@ -120,7 +126,9 @@ class DocComment extends CommentGroup {
  * // Single line comment
  * ```
  */
-class SlashSlashComment extends @slashslashcomment, Comment { }
+class SlashSlashComment extends @slashslashcomment, Comment {
+  override string describeQlClass() { result = "SlashSlashComment" }
+}
 
 /**
  * A block comment starting with `/*` and ending with <code>*&#47;</code>.
@@ -132,7 +140,9 @@ class SlashSlashComment extends @slashslashcomment, Comment { }
  *   comment *&#47
  * </pre>
  */
-class SlashStarComment extends @slashstarcomment, Comment { }
+class SlashStarComment extends @slashstarcomment, Comment {
+  override string describeQlClass() { result = "SlashStarComment" }
+}
 
 /**
  * A single-line comment starting with `//`.
@@ -194,4 +204,6 @@ class BuildConstraintComment extends LineComment {
     // comment text starts with `+build`
     getText().regexpMatch("\\s*\\+build.*")
   }
+
+  override string describeQlClass() { result = "BuildConstraintComment" }
 }

ql/src/semmle/go/Decls.qll

@@ -30,6 +30,8 @@ class Decl extends @decl, ExprParent, StmtParent {
  */
 class BadDecl extends @baddecl, Decl {
   override string toString() { result = "bad declaration" }
+
+  override string describeQlClass() { result = "BadDecl" }
 }
 
 /**
@@ -46,34 +48,44 @@ class GenDecl extends @gendecl, Decl, Documentable {
   int getNumSpec() { result = count(getASpec()) }
 
   override predicate mayHaveSideEffects() { getASpec().mayHaveSideEffects() }
+
+  override string describeQlClass() { result = "GenDecl" }
 }
 
 /**
  * An import declaration.
  */
 class ImportDecl extends @importdecl, GenDecl {
   override string toString() { result = "import declaration" }
+
+  override string describeQlClass() { result = "ImportDecl" }
 }
 
 /**
  * A constant declaration.
  */
 class ConstDecl extends @constdecl, GenDecl {
   override string toString() { result = "constant declaration" }
+
+  override string describeQlClass() { result = "ConstDecl" }
 }
 
 /**
  * A type declaration.
  */
 class TypeDecl extends @typedecl, GenDecl {
   override string toString() { result = "type declaration" }
+
+  override string describeQlClass() { result = "TypeDecl" }
 }
 
 /**
  * A variable declaration.
  */
 class VarDecl extends @vardecl, GenDecl {
   override string toString() { result = "variable declaration" }
+
+  override string describeQlClass() { result = "VarDecl" }
 }
 
 /**
@@ -133,6 +145,8 @@ class FuncDef extends @funcdef, StmtParent, ExprParent {
    * Gets a call to this function.
    */
   DataFlow::CallNode getACall() { result.getACallee() = this }
+
+  override string describeQlClass() { result = "FuncDef" }
 }
 
 /**
@@ -155,6 +169,8 @@ class FuncDecl extends @funcdecl, Decl, Documentable, FuncDef {
   DeclaredFunction getFunction() { this = result.getFuncDecl() }
 
   override string toString() { result = "function declaration" }
+
+  override string describeQlClass() { result = "FuncDecl" }
 }
 
 /**
@@ -219,6 +235,8 @@ class MethodDecl extends FuncDecl {
    * is the variable `p`.
    */
   ReceiverVariable getReceiver() { result.getFunction() = this }
+
+  override string describeQlClass() { result = "MethodDecl" }
 }
 
 /**
@@ -243,6 +261,8 @@ class Spec extends @spec, ExprParent, Documentable {
    * Memory allocation is not considered an observable side effect.
    */
   predicate mayHaveSideEffects() { none() }
+
+  override string describeQlClass() { result = "Spec" }
 }
 
 /**
@@ -262,6 +282,8 @@ class ImportSpec extends @importspec, Spec {
   string getPath() { result = getPathExpr().getValue() }
 
   override string toString() { result = "import specifier" }
+
+  override string describeQlClass() { result = "ImportSpec" }
 }
 
 /**
@@ -344,6 +366,8 @@ class ValueSpec extends @valuespec, Spec {
   override predicate mayHaveSideEffects() { getAnInit().mayHaveSideEffects() }
 
   override string toString() { result = "value declaration specifier" }
+
+  override string describeQlClass() { result = "ValueSpec" }
 }
 
 /**
@@ -360,6 +384,8 @@ class TypeSpec extends @typespec, Spec {
   Expr getTypeExpr() { result = getChildExpr(1) }
 
   override string toString() { result = "type declaration specifier" }
+
+  override string describeQlClass() { result = "TypeSpec" }
 }
 
 /**
@@ -397,13 +423,17 @@ class FieldDecl extends @field, Documentable, ExprParent {
   StructType getDeclaringType() { result = getDeclaringStructTypeExpr().getType() }
 
   override string toString() { result = "field declaration" }
+
+  override string describeQlClass() { result = "FieldDecl" }
 }
 
 /**
  * An embedded field declaration in a struct.
  */
 class EmbeddedFieldDecl extends FieldDecl {
   EmbeddedFieldDecl() { not exists(this.getNameExpr(_)) }
+
+  override string describeQlClass() { result = "EmbeddedFieldDecl" }
 }
 
 /**
@@ -453,6 +483,8 @@ class ParameterDecl extends @field, Documentable, ExprParent {
   }
 
   override string toString() { result = "parameter declaration" }
+
+  override string describeQlClass() { result = "ParameterDecl" }
 }
 
 /**
@@ -482,6 +514,8 @@ class ReceiverDecl extends @field, Documentable, ExprParent {
   Expr getNameExpr() { result = getChildExpr(1) }
 
   override string toString() { result = "receiver declaration" }
+
+  override string describeQlClass() { result = "ReceiverDecl" }
 }
 
 /**
@@ -531,6 +565,8 @@ class ResultVariableDecl extends @field, Documentable, ExprParent {
   int getIndex() { fields(this, _, -(result + 1)) }
 
   override string toString() { result = "result variable declaration" }
+
+  override string describeQlClass() { result = "ResultVariableDecl" }
 }
 
 /**
@@ -579,6 +615,8 @@ class MethodSpec extends InterfaceMemberSpec {
   Expr getNameExpr() { result = name }
 
   override string toString() { result = "method declaration" }
+
+  override string describeQlClass() { result = "MethodSpec" }
 }
 
 /**
@@ -588,4 +626,6 @@ class EmbeddingSpec extends InterfaceMemberSpec {
   EmbeddingSpec() { not exists(getChildExpr(1)) }
 
   override string toString() { result = "interface embedding" }
+
+  override string describeQlClass() { result = "EmbeddingSpec" }
 }