1 files changed, 273 insertions, 0 deletions
diff --git a/js/v8_source_maps.ts b/js/v8_source_maps.ts
new file mode 100644
index 000000000..2384f34dc
--- /dev/null
+++ b/js/v8_source_maps.ts
@@ -0,0 +1,273 @@
+// Copyright 2014 Evan Wallace
+// Copyright 2018 Ryan Dahl <ry@tinyclouds.org>
+// All rights reserved. MIT License.
+// Originated from source-map-support but has been heavily modified for deno.
+import { SourceMapConsumer, MappedPosition } from "source-map";
+import * as base64 from "base64-js";
+import { arrayToStr } from "./util";
+
+const consumers = new Map<string, SourceMapConsumer>();
+
+interface Options {
+  // A callback the returns generated file contents.
+  getGeneratedContents: GetGeneratedContentsCallback;
+  // Usually set the following to true. Set to false for testing.
+  installPrepareStackTrace: boolean;
+}
+
+interface CallSite extends NodeJS.CallSite {
+  getScriptNameOrSourceURL(): string;
+}
+
+interface Position {
+  source: string; // Filename
+  column: number;
+  line: number;
+}
+
+type GetGeneratedContentsCallback = (fileName: string) => string;
+
+let getGeneratedContents: GetGeneratedContentsCallback;
+
+export function install(options: Options) {
+  getGeneratedContents = options.getGeneratedContents;
+  if (options.installPrepareStackTrace) {
+    Error.prepareStackTrace = prepareStackTraceWrapper;
+  }
+}
+
+export function prepareStackTraceWrapper(
+  error: Error,
+  stack: CallSite[]
+): string {
+  try {
+    return prepareStackTrace(error, stack);
+  } catch (prepareStackError) {
+    Error.prepareStackTrace = null;
+    console.log("=====Error inside of prepareStackTrace====");
+    console.log(prepareStackError.stack.toString());
+    console.log("=====Original error=======================");
+    throw error;
+  }
+}
+
+export function prepareStackTrace(error: Error, stack: CallSite[]): string {
+  const frames = stack.map(
+    (frame: CallSite) => `\n    at ${wrapCallSite(frame).toString()}`
+  );
+  return error.toString() + frames.join("");
+}
+
+export function wrapCallSite(frame: CallSite): CallSite {
+  if (frame.isNative()) {
+    return frame;
+  }
+
+  // Most call sites will return the source file from getFileName(), but code
+  // passed to eval() ending in "//# sourceURL=..." will return the source file
+  // from getScriptNameOrSourceURL() instead
+  const source = frame.getFileName() || frame.getScriptNameOrSourceURL();
+
+  if (source) {
+    const line = frame.getLineNumber();
+    const column = frame.getColumnNumber() - 1;
+    const position = mapSourcePosition({ source, line, column });
+    frame = cloneCallSite(frame);
+    frame.getFileName = () => position.source;
+    frame.getLineNumber = () => position.line;
+    frame.getColumnNumber = () => Number(position.column) + 1;
+    frame.getScriptNameOrSourceURL = () => position.source;
+    frame.toString = () => CallSiteToString(frame);
+    return frame;
+  }
+
+  // Code called using eval() needs special handling
+  let origin = frame.isEval() && frame.getEvalOrigin();
+  if (origin) {
+    origin = mapEvalOrigin(origin);
+    frame = cloneCallSite(frame);
+    frame.getEvalOrigin = () => origin;
+    return frame;
+  }
+
+  // If we get here then we were unable to change the source position
+  return frame;
+}
+
+function cloneCallSite(frame: CallSite): CallSite {
+  // tslint:disable:no-any
+  const obj: any = {};
+  const frame_ = frame as any;
+  const props = Object.getOwnPropertyNames(Object.getPrototypeOf(frame));
+  props.forEach(name => {
+    obj[name] = /^(?:is|get)/.test(name)
+      ? () => frame_[name].call(frame)
+      : frame_[name];
+  });
+  return (obj as any) as CallSite;
+  // tslint:enable:no-any
+}
+
+// Taken from source-map-support, original copied from V8's messages.js
+// MIT License. Copyright (c) 2014 Evan Wallace
+function CallSiteToString(frame: CallSite): string {
+  let fileName;
+  let fileLocation = "";
+  if (frame.isNative()) {
+    fileLocation = "native";
+  } else {
+    fileName = frame.getScriptNameOrSourceURL();
+    if (!fileName && frame.isEval()) {
+      fileLocation = frame.getEvalOrigin();
+      fileLocation += ", "; // Expecting source position to follow.
+    }
+
+    if (fileName) {
+      fileLocation += fileName;
+    } else {
+      // Source code does not originate from a file and is not native, but we
+      // can still get the source position inside the source string, e.g. in
+      // an eval string.
+      fileLocation += "<anonymous>";
+    }
+    const lineNumber = frame.getLineNumber();
+    if (lineNumber != null) {
+      fileLocation += ":" + String(lineNumber);
+      const columnNumber = frame.getColumnNumber();
+      if (columnNumber) {
+        fileLocation += ":" + String(columnNumber);
+      }
+    }
+  }
+
+  let line = "";
+  const functionName = frame.getFunctionName();
+  let addSuffix = true;
+  const isConstructor = frame.isConstructor();
+  const isMethodCall = !(frame.isToplevel() || isConstructor);
+  if (isMethodCall) {
+    let typeName = frame.getTypeName();
+    // Fixes shim to be backward compatable with Node v0 to v4
+    if (typeName === "[object Object]") {
+      typeName = "null";
+    }
+    const methodName = frame.getMethodName();
+    if (functionName) {
+      if (typeName && functionName.indexOf(typeName) !== 0) {
+        line += typeName + ".";
+      }
+      line += functionName;
+      if (
+        methodName &&
+        functionName.indexOf("." + methodName) !==
+          functionName.length - methodName.length - 1
+      ) {
+        line += ` [as ${methodName} ]`;
+      }
+    } else {
+      line += typeName + "." + (methodName || "<anonymous>");
+    }
+  } else if (isConstructor) {
+    line += "new " + (functionName || "<anonymous>");
+  } else if (functionName) {
+    line += functionName;
+  } else {
+    line += fileLocation;
+    addSuffix = false;
+  }
+  if (addSuffix) {
+    line += ` (${fileLocation})`;
+  }
+  return line;
+}
+
+// Regex for detecting source maps
+const reSourceMap = /^data:application\/json[^,]+base64,/;
+
+function loadConsumer(source: string): SourceMapConsumer {
+  let consumer = consumers.get(source);
+  if (consumer == null) {
+    const code = getGeneratedContents(source);
+    if (!code) {
+      return null;
+    }
+
+    let sourceMappingURL = retrieveSourceMapURL(code);
+    if (!sourceMappingURL) {
+      throw Error("No source map?");
+    }
+
+    let sourceMapData: string;
+    if (reSourceMap.test(sourceMappingURL)) {
+      // Support source map URL as a data url
+      const rawData = sourceMappingURL.slice(sourceMappingURL.indexOf(",") + 1);
+      const ui8 = base64.toByteArray(rawData);
+      sourceMapData = arrayToStr(ui8);
+      sourceMappingURL = source;
+    } else {
+      // Support source map URLs relative to the source URL
+      //sourceMappingURL = supportRelativeURL(source, sourceMappingURL);
+      sourceMapData = getGeneratedContents(sourceMappingURL);
+    }
+
+    //console.log("sourceMapData", sourceMapData);
+    const rawSourceMap = JSON.parse(sourceMapData);
+    consumer = new SourceMapConsumer(rawSourceMap);
+    consumers.set(source, consumer);
+  }
+  return consumer;
+}
+
+function retrieveSourceMapURL(fileData: string): string {
+  // Get the URL of the source map
+  // tslint:disable-next-line:max-line-length
+  const re = /(?:\/\/[@#][ \t]+sourceMappingURL=([^\s'"]+?)[ \t]*$)|(?:\/\*[@#][ \t]+sourceMappingURL=([^\*]+?)[ \t]*(?:\*\/)[ \t]*$)/gm;
+  // Keep executing the search to find the *last* sourceMappingURL to avoid
+  // picking up sourceMappingURLs from comments, strings, etc.
+  let lastMatch, match;
+  while ((match = re.exec(fileData))) {
+    lastMatch = match;
+  }
+  if (!lastMatch) {
+    return null;
+  }
+  return lastMatch[1];
+}
+
+function mapSourcePosition(position: Position): MappedPosition {
+  const consumer = loadConsumer(position.source);
+  if (consumer == null) {
+    return position;
+  }
+  const mapped = consumer.originalPositionFor(position);
+  return mapped;
+}
+
+// Parses code generated by FormatEvalOrigin(), a function inside V8:
+// https://code.google.com/p/v8/source/browse/trunk/src/messages.js
+function mapEvalOrigin(origin: string): string {
+  // Most eval() calls are in this format
+  let match = /^eval at ([^(]+) \((.+):(\d+):(\d+)\)$/.exec(origin);
+  if (match) {
+    const position = mapSourcePosition({
+      source: match[2],
+      line: Number(match[3]),
+      column: Number(match[4]) - 1
+    });
+    const pos = [
+      position.source,
+      position.line,
+      Number(position.column) + 1
+    ].join(":");
+    return `eval at ${match[1]} (${pos})`;
+  }
+
+  // Parse nested eval() calls using recursion
+  match = /^eval at ([^(]+) \((.+)\)$/.exec(origin);
+  if (match) {
+    return `eval at ${match[1]} (${mapEvalOrigin(match[2])})`;
+  }
+
+  // Make sure we still return useful information if we didn't find anything
+  return origin;
+}