diff --git a/devtools/client/debugger/new/README.mozilla b/devtools/client/debugger/new/README.mozilla
index c1ff730e9428..724d927b58f5 100644
--- a/devtools/client/debugger/new/README.mozilla
+++ b/devtools/client/debugger/new/README.mozilla
@@ -1,9 +1,9 @@
 This is the debugger.html project output.
 See https://github.com/devtools-html/debugger.html
 
-Version 33.0
+Version 34.0
 
-Comparison: https://github.com/devtools-html/debugger.html/compare/release-32...release-33
+Comparison: https://github.com/devtools-html/debugger.html/compare/release-33...release-34
 
 Packages:
 - babel-plugin-transform-es2015-modules-commonjs @6.26.0
diff --git a/devtools/client/debugger/new/debugger.css b/devtools/client/debugger/new/debugger.css
index d8c7a14c7aed..be1ebd8d2a06 100644
--- a/devtools/client/debugger/new/debugger.css
+++ b/devtools/client/debugger/new/debugger.css
@@ -326,18 +326,6 @@ menuseparator {
   --reference-color: var(--theme-highlight-purple);
 }
 
-.theme-firebug {
-  --number-color: #000088;
-  --string-color: #ff0000;
-  --null-color: #787878;
-  --object-color: DarkGreen;
-  --caption-color: #444444;
-  --location-color: #555555;
-  --source-link-color: blue;
-  --node-color: rgb(0, 0, 136);
-  --reference-color: rgb(102, 102, 255);
-}
-
 /******************************************************************************/
 
 .objectLink:hover {
@@ -1078,10 +1066,6 @@ html[dir="rtl"] .tree-node img.arrow {
   font-family: Menlo, monospace;
 }
 
-.project-text-search .result.focused {
-  background-color: var(--search-overlays-semitransparent);
-}
-
 .project-text-search .result .query-match {
   background-color: var(--theme-selection-background);
   color: white;
@@ -1090,10 +1074,6 @@ html[dir="rtl"] .tree-node img.arrow {
   border-radius: 2px;
 }
 
-.project-text-search .result.focused .line-number {
-  font-weight: bolder;
-}
-
 .project-text-search .result .line-number {
   margin-right: 1em;
   width: 2em;
@@ -1121,10 +1101,6 @@ html[dir="rtl"] .tree-node img.arrow {
   margin: 2px 0 2px 0;
 }
 
-.project-text-search .file-result.focused {
-  background-color: var(--search-overlays-semitransparent);
-}
-
 .project-text-search .line-match {
   display: "flex";
   flex-grow: 1;
@@ -1148,6 +1124,22 @@ html[dir="rtl"] .tree-node img.arrow {
 .project-text-search .managed-tree .tree {
   height: 100%;
 }
+
+/* Focus values */
+
+.project-text-search .file-result.focused,
+.project-text-search .result.focused {
+  background-color: var(--theme-selection-background);
+}
+
+.project-text-search .result.focused .line-number {
+  font-weight: bolder;
+}
+
+.project-text-search .result.focused .query-match {
+  background-color: #ffffff;
+  color: #000000;
+}
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
@@ -2925,7 +2917,8 @@ html[dir="rtl"] .breakpoints-list .breakpoint .breakpoint-line {
   display: inline-block;
 }
 
-.CodeMirror.cm-s-mozilla-breakpoint .CodeMirror-code {
+.CodeMirror.cm-s-mozilla-breakpoint .CodeMirror-code,
+.CodeMirror.cm-s-mozilla-breakpoint .CodeMirror-scroll {
   cursor: default;
 }
 /* This Source Code Form is subject to the terms of the Mozilla Public
@@ -3009,10 +3002,6 @@ html[dir="rtl"] .breakpoints-list .breakpoint .breakpoint-line {
   background-color: var(--theme-selection-background-hover);
 }
 
-:root.theme-firebug .expression-container:hover {
-  background-color: var(--theme-selection-background-hover);
-}
-
 .tree  .tree-node:not(.focused):hover {
   background-color: transparent;
 }
@@ -3158,8 +3147,7 @@ html[dir="rtl"] .breakpoints-list .breakpoint .breakpoint-line {
   flex-shrink: 0;
 }
 
-.theme-light .frames .location,
-.theme-firebug .frames .location {
+.theme-light .frames .location {
   color: var(--theme-comment);
 }
 
@@ -3194,7 +3182,6 @@ html[dir="rtl"] .breakpoints-list .breakpoint .breakpoint-line {
 }
 
 :root.theme-light .frames ul li.selected .location,
-:root.theme-firebug .frames ul li.selected .location,
 :root.theme-dark .frames ul li.selected .location {
   color: white;
 }
@@ -4067,7 +4054,6 @@ html .welcomebox .toggle-button-end.collapsed {
   line-height: 1.5em;
   word-break: break-all;
   text-overflow: ellipsis;
-  overflow: hidden;
   white-space: nowrap;
 }
 
diff --git a/devtools/client/debugger/new/debugger.js b/devtools/client/debugger/new/debugger.js
index 284d7d2dc484..fa96b23e98d3 100644
--- a/devtools/client/debugger/new/debugger.js
+++ b/devtools/client/debugger/new/debugger.js
@@ -5113,6 +5113,14 @@ function showSource(sourceId) {
   return ({ dispatch, getState }) => {
     const source = (0, _selectors.getSource)(getState(), sourceId);
 
+    if ((0, _selectors.getPaneCollapse)(getState(), "start")) {
+      dispatch({
+        type: "TOGGLE_PANE",
+        position: "start",
+        paneCollapsed: false
+      });
+    }
+
     dispatch(setPrimaryPaneTab("sources"));
     dispatch({
       type: "SHOW_SOURCE",
@@ -6433,10 +6441,7 @@ function getMappedExpression(expression) {
       return expression;
     }
 
-    return await dispatch({
-      type: "MAP_EXPRESSION_RESULT",
-      [_promise.PROMISE]: parser.mapOriginalExpression(expression, mappings)
-    });
+    return parser.mapOriginalExpression(expression, mappings);
   };
 }
 
@@ -6616,14 +6621,31 @@ var _WasmDis = __webpack_require__(678);
 
 var wasmStates = Object.create(null);
 
+function maybeWasmSectionNameResolver(data) {
+  try {
+    const parser = new _WasmParser.BinaryReader();
+    parser.setData(data.buffer, 0, data.length);
+    const reader = new _WasmDis.NameSectionReader();
+    reader.read(parser);
+    return reader.hasValidNames() ? reader.getNameResolver() : null;
+  } catch (ex) {
+    // Ignoring any errors during names section retrival.
+    return null;
+  }
+}
+
 /**
  * @memberof utils/wasm
  * @static
  */
 function getWasmText(sourceId, data) {
+  const nameResolver = maybeWasmSectionNameResolver(data);
   const parser = new _WasmParser.BinaryReader();
   parser.setData(data.buffer, 0, data.length);
   const dis = new _WasmDis.WasmDisassembler();
+  if (nameResolver) {
+    dis.nameResolver = nameResolver;
+  }
   dis.addOffsets = true;
   const done = dis.disassembleChunk(parser);
   let result = dis.getResult();
@@ -7019,9 +7041,18 @@ class ManagedTree extends _react.Component {
     if (expanded.has(this.props.getPath(highlightItems[0]))) {
       this.focusItem(highlightItems[0]);
     } else {
-      // Look at folders starting from the top-level until finds a
-      // closed folder and highlights this folder
-      const index = highlightItems.reverse().findIndex(item => !expanded.has(this.props.getPath(item)));
+      // Look at folders starting from the top-level and expand all the items
+      // which lie in the path of the item to be highlighted
+      highlightItems.reverse();
+      let index = highlightItems.findIndex(item => !expanded.has(this.props.getPath(item)));
+
+      if (this.props.autoExpandOnHighlight) {
+        while (index < highlightItems.length - 1) {
+          this.setExpanded(highlightItems[index], true, false);
+          index++;
+        }
+      }
+
       this.focusItem(highlightItems[index]);
     }
   }
@@ -7103,7 +7134,7 @@ function getURL(sourceUrl, debuggeeUrl = "") {
       // A Webpack source is a special case
       return (0, _lodash.merge)(def, {
         path: path,
-        group: "Webpack",
+        group: "webpack://",
         filename: filename
       });
 
@@ -7111,7 +7142,7 @@ function getURL(sourceUrl, debuggeeUrl = "") {
       // An Angular source is a special case
       return (0, _lodash.merge)(def, {
         path: path,
-        group: "Angular",
+        group: "ng://",
         filename: filename
       });
 
@@ -9892,7 +9923,7 @@ function isUnderRoot(url, projectRoot) {
     return true;
   }
 
-  return `/${url.group}${url.path}`.startsWith(projectRoot);
+  return `${url.group}${url.path}`.startsWith(projectRoot);
 } /* This Source Code Form is subject to the terms of the Mozilla Public
    * License, v. 2.0. If a copy of the MPL was not distributed with this
    * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
@@ -9958,7 +9989,7 @@ function traverseTree(url, tree, debuggeeHost, projectRoot) {
 
   let path = "";
   return parts.reduce((subTree, part, index) => {
-    path = `${path}/${part}`;
+    path = path ? `${path}/${part}` : part;
     const debuggeeHostIfRoot = index === 0 ? debuggeeHost : null;
     return findOrCreateNode(parts, subTree, path, part, index, url, debuggeeHostIfRoot);
   }, tree);
@@ -12874,8 +12905,12 @@ var _pause = __webpack_require__(1394);
 
 var _sources = __webpack_require__(1369);
 
-function visibleSourceId(location) {
-  return (0, _devtoolsSourceMap.isOriginalId)(location.sourceId) ? (0, _devtoolsSourceMap.originalToGeneratedId)(location.sourceId) : location.sourceId;
+function getGeneratedId(sourceId) {
+  if ((0, _devtoolsSourceMap.isOriginalId)(sourceId)) {
+    return (0, _devtoolsSourceMap.originalToGeneratedId)(sourceId);
+  }
+
+  return sourceId;
 }
 
 /*
@@ -12894,7 +12929,11 @@ function isSelectedFrameVisible(state) {
     return false;
   }
 
-  return visibleSourceId(selectedLocation) === visibleSourceId(selectedFrame.location);
+  if ((0, _devtoolsSourceMap.isOriginalId)(selectedLocation.sourceId)) {
+    return selectedLocation.sourceId === selectedFrame.location.sourceId;
+  }
+
+  return selectedLocation.sourceId === getGeneratedId(selectedFrame.location.sourceId);
 }
 
 /***/ }),
@@ -16159,7 +16198,7 @@ function findSource(sourceTree, sourceUrl) {
 
 function getDirectories(sourceUrl, sourceTree) {
   const url = (0, _getURL.getURL)(sourceUrl);
-  const fullUrl = `/${url.group}${url.path}`;
+  const fullUrl = `${url.group}${url.path}`;
   const parentMap = (0, _utils.createParentMap)(sourceTree);
   const source = findSource(sourceTree, fullUrl);
   if (!source) {
@@ -16737,6 +16776,15 @@ class SourcesTree extends _react.Component {
     }
   }
 
+  renderItemName(name) {
+    const hosts = {
+      "ng://": "Angular",
+      "webpack://": "Webpack"
+    };
+
+    return hosts[name] || name;
+  }
+
   renderEmptyElement(message) {
     return _react2.default.createElement(
       "div",
@@ -16803,6 +16851,7 @@ class SourcesTree extends _react.Component {
     const treeProps = {
       autoExpandAll: false,
       autoExpandDepth: expanded ? 0 : 1,
+      autoExpandOnHighlight: true,
       expanded,
       getChildren: item => (0, _sourcesTree.nodeHasChildren)(item) ? item.contents : [],
       getParent: item => parentMap.get(item),
@@ -16874,7 +16923,7 @@ var _initialiseProps = function () {
   this.getIcon = (sources, item, depth) => {
     const { debuggeeUrl, projectRoot } = this.props;
 
-    if (item.path === "/Webpack") {
+    if (item.path === "webpack://") {
       return _react2.default.createElement(_Svg2.default, { name: "webpack" });
     }
     if (item.path === "/Angular") {
@@ -16986,7 +17035,7 @@ var _initialiseProps = function () {
         "span",
         { className: "label" },
         " ",
-        item.name,
+        this.renderItemName(item.name),
         " "
       )
     );
@@ -18295,9 +18344,7 @@ class Preview extends _react.PureComponent {
 
     this.onMouseOver = e => {
       const { target } = e;
-      if (this.props.selectedFrameVisible) {
-        this.props.updatePreview(target, this.props.editor);
-      }
+      this.props.updatePreview(target, this.props.editor);
     };
 
     this.onMouseUp = () => {
@@ -18384,8 +18431,7 @@ const {
 
 exports.default = (0, _reactRedux.connect)(state => ({
   preview: (0, _selectors.getPreview)(state),
-  selectedSource: (0, _selectors.getSelectedSource)(state),
-  selectedFrameVisible: (0, _selectors.isSelectedFrameVisible)(state)
+  selectedSource: (0, _selectors.getSelectedSource)(state)
 }), {
   addExpression,
   setPopupObjectProperties,
@@ -30462,7 +30508,7 @@ function updatePreview(target, editor) {
       return;
     }
 
-    if (!(0, _selectors.isLineInScope)(getState(), tokenPos.line)) {
+    if (!(0, _selectors.isSelectedFrameVisible)(getState()) || !(0, _selectors.isLineInScope)(getState(), tokenPos.line)) {
       return;
     }
 
@@ -38777,7 +38823,6 @@ function formatSource(source, root) {
 function getRelativeSources(state) {
   const sources = (0, _selectors.getSources)(state);
   const root = (0, _selectors.getProjectDirectoryRoot)(state);
-
   return sources.valueSeq().toJS().filter(({ url }) => url && url.includes(root)).map(source => formatSource(source, root));
 }
 
@@ -38986,6 +39031,7 @@ class BreakpointItem extends _react.Component {
         // $FlowIgnore
         mountNode.innerHTML = "";
         this.editor.appendToLocalElement(mountNode);
+        this.editor.codeMirror.on("mousedown", (_, e) => e.preventDefault());
       }
     }
   }
diff --git a/devtools/client/debugger/new/test/mochitest/browser_dbg-asm.js b/devtools/client/debugger/new/test/mochitest/browser_dbg-asm.js
index b55df7ff1bd3..955eff511482 100644
--- a/devtools/client/debugger/new/test/mochitest/browser_dbg-asm.js
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg-asm.js
@@ -9,10 +9,6 @@ add_task(async function() {
 
   await waitForSources(dbg, "doc-asm.html", "asm.js");
 
-  // Expand nodes and make sure more sources appear.
-  is(findAllElements(dbg, "sourceNodes").length, 2);
-
-  await clickElement(dbg, "sourceDirectoryLabel", 2);
   is(findAllElements(dbg, "sourceNodes").length, 4);
 
   await selectSource(dbg, "asm.js");
diff --git a/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-preview.js b/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-preview.js
index 3fdaa74bbfb1..3662e5a1b03f 100644
--- a/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-preview.js
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-preview.js
@@ -1,6 +1,9 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
+// Tests for preview through Babel's compile output.
+requestLongerTimeout(3);
+
 function getCoordsFromPosition(cm, { line, ch }) {
   return cm.charCoords({ line: ~~line, ch: ~~ch });
 }
diff --git a/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-scopes.js b/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-scopes.js
index 08885357165b..34a1458804dc 100644
--- a/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-scopes.js
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg-babel-scopes.js
@@ -2,7 +2,7 @@
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
 // This test can be really slow on debug platforms and should be split.
-requestLongerTimeout(4);
+requestLongerTimeout(6);
 
 // Tests loading sourcemapped sources for Babel's compile output.
 
diff --git a/devtools/client/debugger/new/test/mochitest/browser_dbg-preview-source-maps.js b/devtools/client/debugger/new/test/mochitest/browser_dbg-preview-source-maps.js
index 54be37beace1..d3d04eca6b9a 100644
--- a/devtools/client/debugger/new/test/mochitest/browser_dbg-preview-source-maps.js
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg-preview-source-maps.js
@@ -1,24 +1,11 @@
 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/ */
 
-function getCoordsFromPosition(cm, { line, ch }) {
-  return cm.charCoords({ line: ~~line, ch: ~~ch });
-}
 
-function hoverAtPos(dbg, { line, ch }) {
-  info(`Hovering at (${line}, ${ch})\n`);
-  const cm = getCM(dbg);
-  const coords = getCoordsFromPosition(cm, { line: line - 1, ch });
-  const tokenEl = dbg.win.document.elementFromPoint(coords.left, coords.top);
-  const previewed = waitForDispatch(dbg, "SET_PREVIEW");
-  tokenEl.dispatchEvent(
-    new MouseEvent("mouseover", {
-      bubbles: true,
-      cancelable: true,
-      view: dbg.win
-    })
-  );
-  return previewed;
+async function assertNoTooltip(dbg) {
+  await waitForTime(200);
+  const el = findElement(dbg, "tooltip");
+  is(el, null, "Tooltip should not exist")
 }
 
 function assertPreviewTooltip(dbg, { result, expression }) {
@@ -58,12 +45,21 @@ add_task(async function() {
   await waitForPaused(dbg);
   await waitForSelectedSource(dbg, "times2");
 
-  await hoverAtPos(dbg, { line: 2, ch: 9 });
-  assertPreviewTooltip(dbg, { result: 4, expression: "x" });
+  info(`Test previewing in the original location`)
+  await assertPreviews(dbg, [
+    { line: 2, column: 10, result: 4, expression: "x" }
+  ]);
 
+  info(`Test previewing in the generated location`)
   await dbg.actions.jumpToMappedSelectedLocation();
   await waitForSelectedSource(dbg, "bundle.js");
+  await assertPreviews(dbg, [
+    { line: 70, column: 11, result: 4, expression: "x" }
+  ]);
 
-  await hoverAtPos(dbg, { line: 70, ch: 10 });
-  assertPreviewTooltip(dbg, { result: 4, expression: "x" });
+
+  info(`Test that you can not preview in another original file`);
+  await selectSource(dbg, "output");
+  await hoverAtPos(dbg, { line: 2, ch: 16 });
+  await assertNoTooltip(dbg)
 });
diff --git a/devtools/client/debugger/new/test/mochitest/browser_dbg-sources.js b/devtools/client/debugger/new/test/mochitest/browser_dbg-sources.js
index 8f485f8446a8..191d7734baa3 100644
--- a/devtools/client/debugger/new/test/mochitest/browser_dbg-sources.js
+++ b/devtools/client/debugger/new/test/mochitest/browser_dbg-sources.js
@@ -22,6 +22,23 @@ function getLabel(dbg, index) {
     .replace(/^[\s\u200b]*/g, "");
 }
 
+add_task(async function() {
+  const dbg = await initDebugger("doc-sources.html");
+  const { selectors: { getSelectedSource, getExpandedState }, getState } = dbg;
+
+  await waitForSources(dbg, "nested-source");
+  await selectSource(dbg, "nested-source");
+
+  const expanded = getExpandedState(getState());
+
+  ok(
+    expanded.has(
+      `example.com/browser/devtools/client/debugger/new/test/mochitest/examples/nested/nested/`
+    ),
+    "Nodes in path are automatically expanded"
+  );
+});
+
 add_task(async function() {
   const dbg = await initDebugger("doc-sources.html");
   const { selectors: { getSelectedSource }, getState } = dbg;
diff --git a/devtools/client/shared/vendor/WASMPARSER_UPGRADING b/devtools/client/shared/vendor/WASMPARSER_UPGRADING
index f7168833bbc1..4fc423890bfe 100644
--- a/devtools/client/shared/vendor/WASMPARSER_UPGRADING
+++ b/devtools/client/shared/vendor/WASMPARSER_UPGRADING
@@ -1,13 +1,13 @@
 # wasmparser version
 
-Current vesion is: 0.5.3
+Current vesion is: 0.6.0
 
 # Upgrade process
 
 1. Pull latest release from npm and extract WasmDis.js and WasmParser.js, e.g.
 
 ```
-curl https://registry.npmjs.org/wasmparser/-/wasmparser-0.5.3.tgz | tar -x --strip-components 2 package/dist/{WasmDis,WasmParser}.js
+curl https://registry.npmjs.org/wasmparser/-/wasmparser-0.6.0.tgz | tar -x --strip-components 2 package/dist/{WasmDis,WasmParser}.js
 ```
 
 2. Remove reference to source maps (last line)
diff --git a/devtools/client/shared/vendor/WasmDis.js b/devtools/client/shared/vendor/WasmDis.js
index fbb528f50f99..0a73193e1cea 100644
--- a/devtools/client/shared/vendor/WasmDis.js
+++ b/devtools/client/shared/vendor/WasmDis.js
@@ -1,4 +1,14 @@
 "use strict";
+var __extends = (this && this.__extends) || (function () {
+    var extendStatics = Object.setPrototypeOf ||
+        ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
+        function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
+    return function (d, b) {
+        extendStatics(d, b);
+        function __() { this.constructor = d; }
+        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+    };
+})();
 Object.defineProperty(exports, "__esModule", { value: true });
 /* Copyright 2016 Mozilla Foundation
  *
@@ -981,3 +991,119 @@ var WasmDisassembler = /** @class */ (function () {
     return WasmDisassembler;
 }());
 exports.WasmDisassembler = WasmDisassembler;
+var UNKNOWN_FUNCTION_PREFIX = "unknown";
+var NameSectionNameResolver = /** @class */ (function (_super) {
+    __extends(NameSectionNameResolver, _super);
+    function NameSectionNameResolver(names) {
+        var _this = _super.call(this) || this;
+        _this._names = names;
+        return _this;
+    }
+    NameSectionNameResolver.prototype.getFunctionName = function (index, isImport, isRef) {
+        var name = this._names[index];
+        if (!name)
+            return "$" + UNKNOWN_FUNCTION_PREFIX + index;
+        return isRef ? "$" + name : "$" + name + " (;" + index + ";)";
+    };
+    return NameSectionNameResolver;
+}(DefaultNameResolver));
+var NameSectionReader = /** @class */ (function () {
+    function NameSectionReader() {
+        this._done = false;
+        this._functionsCount = 0;
+        this._functionImportsCount = 0;
+        this._functionNames = null;
+        this._hasNames = false;
+    }
+    NameSectionReader.prototype.read = function (reader) {
+        var _this = this;
+        if (this._done)
+            throw new Error('Invalid state: disassembly process was already finished.');
+        while (true) {
+            if (!reader.read())
+                return false;
+            switch (reader.state) {
+                case 2 /* END_WASM */:
+                    if (!reader.hasMoreBytes()) {
+                        this._done = true;
+                        return true;
+                    }
+                    break;
+                case -1 /* ERROR */:
+                    throw reader.error;
+                case 1 /* BEGIN_WASM */:
+                    this._functionsCount = 0;
+                    this._functionImportsCount = 0;
+                    this._functionNames = [];
+                    this._hasNames = false;
+                    break;
+                case 4 /* END_SECTION */:
+                    break;
+                case 3 /* BEGIN_SECTION */:
+                    var sectionInfo = reader.result;
+                    if (sectionInfo.id === 0 /* Custom */ &&
+                        WasmParser_1.bytesToString(sectionInfo.name) === "name") {
+                        break;
+                    }
+                    if (sectionInfo.id === 3 /* Function */ ||
+                        sectionInfo.id === 2 /* Import */) {
+                        break;
+                    }
+                    reader.skipSection();
+                    break;
+                case 12 /* IMPORT_SECTION_ENTRY */:
+                    var importInfo = reader.result;
+                    if (importInfo.kind === 0 /* Function */)
+                        this._functionImportsCount++;
+                    break;
+                case 13 /* FUNCTION_SECTION_ENTRY */:
+                    this._functionsCount++;
+                    break;
+                case 19 /* NAME_SECTION_ENTRY */:
+                    var nameInfo = reader.result;
+                    if (nameInfo.type !== 1 /* Function */)
+                        break;
+                    var functionNameInfo = nameInfo;
+                    functionNameInfo.names.forEach(function (naming) {
+                        _this._functionNames[naming.index] = WasmParser_1.bytesToString(naming.name);
+                    });
+                    this._hasNames = true;
+                    break;
+                default:
+                    throw new Error("Expectected state: " + reader.state);
+            }
+        }
+    };
+    NameSectionReader.prototype.hasValidNames = function () {
+        return this._hasNames;
+    };
+    NameSectionReader.prototype.getNameResolver = function () {
+        if (!this.hasValidNames())
+            throw new Error("Has no valid name section");
+        // Fix bad names.
+        var functionNamesLength = this._functionImportsCount + this._functionsCount;
+        var functionNames = this._functionNames.slice(0, functionNamesLength);
+        var usedNameAt = Object.create(null);
+        for (var i = 0; i < functionNames.length; i++) {
+            var name_1 = functionNames[i];
+            if (!name_1)
+                continue;
+            var goodName = !(name_1 in usedNameAt) &&
+                !/[^0-9A-Za-z!#$%&'*+.:<=>?@^_`|~\/\-]/.test(name_1) &&
+                name_1.indexOf(UNKNOWN_FUNCTION_PREFIX) !== 0;
+            if (!goodName) {
+                if (usedNameAt[name_1] >= 0) {
+                    // Remove all non-unique names.
+                    functionNames[usedNameAt[name_1]] = null;
+                    usedNameAt[name_1] = -1;
+                }
+                functionNames[i] = null;
+                continue;
+            }
+            usedNameAt[name_1] = i;
+        }
+        return new NameSectionNameResolver(functionNames);
+    };
+    return NameSectionReader;
+}());
+exports.NameSectionReader = NameSectionReader;