Strip more unused features.

lib/merge.ts

Index: lib/merge.ts
diff --git a/lib/merge.ts b/lib/merge.ts
new file mode 100644
index 0000000000000000000000000000000000000000..0b9c8d746496b1608dd7eb08d7b35a25735520ed
--- /dev/null
+++ b/lib/merge.ts
@@ -0,0 +1,322 @@
+import ts = require('typescript');
+import base = require('./base');
+import {FacadeConverter} from './facade_converter';
+
+/**
+ * To support arbitrary d.ts files in Dart we often have to merge two TypeScript
+ * types into a single Dart type because Dart lacks features such as method
+ * overloads, type aliases, and union types.
+ */
+export class MergedType {
+  constructor(private fc: FacadeConverter) {}
+
+  merge(t?: ts.TypeNode) {
+    if (t) {
+      // TODO(jacobr): get a better unique name for a type.
+      switch (t.kind) {
+        case ts.SyntaxKind.UnionType:
+          let union = <ts.UnionTypeNode>t;
+          union.types.forEach(this.merge.bind(this));
+          return;
+        case ts.SyntaxKind.LastTypeNode:
+          this.merge((t as ts.ParenthesizedTypeNode).type);
+          return;
+        case ts.SyntaxKind.TypePredicate:
+          this.merge((t as ts.TypePredicateNode).type);
+          return;
+        case ts.SyntaxKind.TypeReference:
+          // We need to follow Alais types as Dart does not support them for non
+          // function types. TODO(jacobr): handle them for Function types?
+          let typeRef = <ts.TypeReferenceNode>t;
+          let decl = this.fc.getDeclaration(typeRef.typeName);
+          if (decl !== null && decl.kind === ts.SyntaxKind.TypeAliasDeclaration) {
+            let alias = <ts.TypeAliasDeclaration>decl;
+
+            if (typeRef.typeArguments) {
+              throw 'TypeReference with arguements not supported yet:' + t.getText();
+            }
+
+            this.merge(alias.type);
+            return;
+          }
+          break;
+        default:
+          break;
+      }
+      this.types[this.fc.generateDartTypeName(t, true)] = t;
+    }
+  }
+
+  toTypeNode(): ts.TypeNode {
+    let names = Object.getOwnPropertyNames(this.types);
+    if (names.length === 0) {
+      return null;
+    }
+    if (names.length === 1) {
+      return this.types[names[0]];
+    }
+    let union = <ts.UnionTypeNode>ts.createNode(ts.SyntaxKind.UnionType);
+    base.copyLocation(this.types[names[0]], union);
+
+    union.types = <ts.NodeArray<ts.TypeNode>>[];
+    for (let i = 0; i < names.length; ++i) {
+      union.types.push(this.types[names[i]]);
+    }
+    return union;
+  }
+
+  private types: {[name: string]: ts.TypeNode} = {};
+}
+
+/**
+ * Handle a parameter that is the result of merging parameter declarations from
+ * multiple method overloads.
+ */
+export class MergedParameter {
+  constructor(param: ts.ParameterDeclaration, fc: FacadeConverter) {
+    this.type = new MergedType(fc);
+    this.textRange = param;
+    this.merge(param);
+  }
+
+  merge(param: ts.ParameterDeclaration) {
+    this.name[base.ident(param.name)] = true;
+    if (!this.optional) {
+      this.optional = !!param.questionToken;
+    }
+    this.type.merge(param.type);
+  }
+
+  toParameterDeclaration(): ts.ParameterDeclaration {
+    let ret = <ts.ParameterDeclaration>ts.createNode(ts.SyntaxKind.Parameter);
+    let nameIdentifier = <ts.Identifier>ts.createNode(ts.SyntaxKind.Identifier);
+    nameIdentifier.text = Object.getOwnPropertyNames(this.name).join('_');
+    ret.name = nameIdentifier;
+    if (this.optional) {
+      ret.questionToken = ts.createNode(ts.SyntaxKind.QuestionToken);
+    }
+    base.copyLocation(this.textRange, ret);
+    ret.type = this.type.toTypeNode();
+    return ret;
+  }
+
+  setOptional() { this.optional = true; }
+
+  private name: {[s: string]: boolean} = {};
+  private type: MergedType;
+  private optional: boolean = false;
+  private textRange: ts.TextRange;
+}
+
+/**
+ * Normalize a SourceFile
+ */
+export function normalizeSourceFile(f: ts.SourceFile) {
+  let modules: {[name: string]: ts.ModuleDeclaration} = {};
+
+  // Merge top level modules.
+  for (let i = 0; i < f.statements.length; ++i) {
+    let statement = f.statements[i];
+    if (statement.kind !== ts.SyntaxKind.ModuleDeclaration) continue;
+    let moduleDecl = <ts.ModuleDeclaration>statement;
+    let name = moduleDecl.name.text;
+    if (modules.hasOwnProperty(name)) {
+      let srcBody = modules[name].body;
+      let srcBodyBlock: ts.ModuleBlock;
+
+      if (srcBody.kind !== ts.SyntaxKind.ModuleBlock) {
+        throw 'Module body must be a module block.';
+      }
+      srcBodyBlock = <ts.ModuleBlock>srcBody;
+
+      let body = moduleDecl.body;
+      if (body.kind === ts.SyntaxKind.ModuleBlock) {
+        let bodyBlock = <ts.ModuleBlock>body;
+        Array.prototype.push.apply(srcBodyBlock.statements, bodyBlock.statements);
+      } else {
+        // moduleDecl.body is a ModuleDeclaration.
+        srcBodyBlock.statements.push(moduleDecl.body);
+      }
+
+      f.statements.splice(i, 1);
+      i--;
+    } else {
+      modules[name] = moduleDecl;
+    }
+  }
+
+  function addModifier(n: ts.Node, modifier: ts.Node) {
+    if (!n.modifiers) {
+      n.modifiers = <ts.ModifiersArray>[];
+      n.modifiers.flags = 0;
+    }
+    modifier.parent = n;
+    n.modifiers.push(modifier);
+  }
+
+  function mergeVariablesIntoClasses(n: ts.Node, classes: {[name: string]: base.ClassLike}) {
+    switch (n.kind) {
+      case ts.SyntaxKind.VariableStatement:
+        let statement = <ts.VariableStatement>n;
+        statement.declarationList.declarations.forEach(function(
+            declaration: ts.VariableDeclaration) {
+          if (declaration.name.kind === ts.SyntaxKind.Identifier) {
+            let name: string = (<ts.Identifier>(declaration.name)).text;
+            if (classes.hasOwnProperty(name)) {
+              let existing = classes[name];
+              let members = existing.members as Array<ts.ClassElement>;
+              if (declaration.type) {
+                let type: ts.TypeNode = declaration.type;
+                if (type.kind === ts.SyntaxKind.TypeLiteral) {
+                  removeNode(n);
+                  let literal = <ts.TypeLiteralNode>type;
+                  literal.members.forEach((member: ts.Node) => {
+                    switch (member.kind) {
+                      case ts.SyntaxKind.ConstructSignature:
+                        let signature: any = member;
+                        let constructor =
+                            <ts.ConstructorDeclaration>ts.createNode(ts.SyntaxKind.Constructor);
+                        constructor.parameters = signature.parameters;
+                        constructor.type = signature.type;
+                        base.copyLocation(signature, constructor);
+                        constructor.typeParameters = signature.typeParameters;
+                        constructor.parent = existing;
+                        members.push(<ts.ClassElement>constructor);
+                        break;
+                      case ts.SyntaxKind.Constructor:
+                        member.parent = existing.parent;
+                        members.push(<ts.ClassElement>member);
+                        break;
+                      case ts.SyntaxKind.MethodSignature:
+                        member.parent = existing.parent;
+                        members.push(<ts.ClassElement>member);
+                        break;
+                      case ts.SyntaxKind.PropertySignature:
+                        addModifier(member, ts.createNode(ts.SyntaxKind.StaticKeyword));
+                        member.parent = existing;
+                        members.push(<ts.ClassElement>member);
+                        break;
+                      case ts.SyntaxKind.IndexSignature:
+                        member.parent = existing.parent;
+                        members.push(<ts.ClassElement>member);
+                        break;
+                      case ts.SyntaxKind.CallSignature:
+                        member.parent = existing.parent;
+                        members.push(<ts.ClassElement>member);
+                        break;
+                      default:
+                        throw 'Unhandled TypeLiteral member type:' + member.kind;
+                    }
+                  });
+                }
+              }
+            }
+          } else {
+            throw 'Unexpected VariableStatement identifier kind';
+          }
+        });
+        break;
+      case ts.SyntaxKind.ModuleBlock:
+        ts.forEachChild(n, (child) => mergeVariablesIntoClasses(child, classes));
+        break;
+      default:
+        break;
+    }
+  }
+
+  function removeFromArray(nodes: ts.NodeArray<ts.Node>, v: ts.Node) {
+    for (let i = 0, len = nodes.length; i < len; ++i) {
+      if (nodes[i] === v) {
+        nodes.splice(i, 1);
+        break;
+      }
+    }
+  }
+
+  function removeNode(n: ts.Node) {
+    let parent = n.parent;
+    switch (parent.kind) {
+      case ts.SyntaxKind.ModuleBlock:
+        let block = <ts.ModuleBlock>parent;
+        removeFromArray(block.statements, n);
+        break;
+      case ts.SyntaxKind.SourceFile:
+        let sourceFile = <ts.SourceFile>parent;
+        removeFromArray(sourceFile.statements, n);
+        break;
+      default:
+        throw 'removeNode not implemented for kind:' + parent.kind;
+    }
+  }
+
+  function makeCallableClassesImplementFunction(decl: base.ClassLike) {
+    if (base.isCallable(decl)) {
+      // Modify the AST to explicitly state that the class implements Function
+      if (!decl.heritageClauses) {
+        decl.heritageClauses = <ts.NodeArray<ts.HeritageClause>>[];
+        base.copyLocation(decl, decl.heritageClauses);
+      }
+      let clauses = decl.heritageClauses;
+      let clause = base.arrayFindPolyfill(
+          clauses, (c) => c.token !== ts.SyntaxKind.ExtendsKeyword ||
+              decl.kind === ts.SyntaxKind.InterfaceDeclaration);
+      if (clause == null) {
+        clause = <ts.HeritageClause>ts.createNode(ts.SyntaxKind.HeritageClause);
+        clause.token = decl.kind === ts.SyntaxKind.InterfaceDeclaration ?
+            ts.SyntaxKind.ExtendsKeyword :
+            ts.SyntaxKind.ImplementsKeyword;
+        clause.types = <ts.NodeArray<ts.ExpressionWithTypeArguments>>[];
+        clause.parent = decl;
+        base.copyLocation(decl, clause);
+        clauses.push(clause);
+      }
+      let functionType =
+          <ts.ExpressionWithTypeArguments>ts.createNode(ts.SyntaxKind.ExpressionWithTypeArguments);
+      functionType.parent = clause;
+      base.copyLocation(clause, functionType);
+      let fn = <ts.Identifier>ts.createNode(ts.SyntaxKind.Identifier);
+      fn.text = 'Function';
+      fn.parent = functionType;
+      base.copyLocation(functionType, fn);
+      functionType.expression = fn;
+      clause.types.push(functionType);
+    }
+  }
+
+  function gatherClasses(n: ts.Node, classes: {[name: string]: base.ClassLike}) {
+    switch (n.kind) {
+      case ts.SyntaxKind.ClassDeclaration:
+      case ts.SyntaxKind.InterfaceDeclaration:
+        let classDecl = <base.ClassLike>n;
+        let name = classDecl.name.text;
+        // TODO(jacobr): validate that the classes have consistent
+        // modifiers, etc.
+        if (classes.hasOwnProperty(name)) {
+          let existing = classes[name];
+          (classDecl.members as Array<ts.ClassElement>).forEach((e: ts.ClassElement) => {
+            (existing.members as Array<ts.ClassElement>).push(e);
+            e.parent = existing;
+          });
+          removeNode(classDecl);
+        } else {
+          classes[name] = classDecl;
+          // Perform other class level post processing here.
+          makeCallableClassesImplementFunction(classDecl);
+        }
+        break;
+      case ts.SyntaxKind.ModuleDeclaration:
+      case ts.SyntaxKind.SourceFile:
+        let moduleClasses: {[name: string]: base.ClassLike} = {};
+        ts.forEachChild(n, (child) => gatherClasses(child, moduleClasses));
+        ts.forEachChild(n, (child) => mergeVariablesIntoClasses(child, moduleClasses));
+
+        break;
+      case ts.SyntaxKind.ModuleBlock:
+        ts.forEachChild(n, (child) => gatherClasses(child, classes));
+        break;
+      default:
+        break;
+    }
+  }
+  gatherClasses(f, {});
+}