handle `source-map` operations internally (#3754)

11 files changed, 173 insertions, 89 deletions

diff --git a/lib/minify.js b/lib/minify.js
index 72d99576..ab397f5e 100644
--- a/lib/minify.js
+++ b/lib/minify.js
@@ -203,6 +203,7 @@ function minify(files, options) {
         if (!HOP(options.output, "code") || options.output.code) {
             if (options.sourceMap) {
                 options.output.source_map = SourceMap({
+                    content: options.sourceMap.includeSources,
                     file: options.sourceMap.filename,
                     orig: source_maps,
                     root: options.sourceMap.root
@@ -211,10 +212,8 @@ function minify(files, options) {
                     if (files instanceof AST_Toplevel) {
                         throw new Error("original source content unavailable");
                     } else for (var name in files) if (HOP(files, name)) {
-                        options.output.source_map.get().setSourceContent(name, files[name]);
+                        options.output.source_map.setSourceContent(name, files[name]);
                     }
-                } else {
-                    options.output.source_map.get()._sourcesContents = null;
                 }
             }
             delete options.output.ast;
diff --git a/lib/sourcemap.js b/lib/sourcemap.js
index 2feec45d..3ca9f9a8 100644
--- a/lib/sourcemap.js
+++ b/lib/sourcemap.js
@@ -43,62 +43,144 @@
 
 "use strict";
 
-// a small wrapper around fitzgen's source-map library
+var vlq_char = characters("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/");
+var vlq_bits = vlq_char.reduce(function(map, ch, bits) {
+    map[ch] = bits;
+    return map;
+}, Object.create(null));
+
+function vlq_decode(indices, str) {
+    var value = 0;
+    var shift = 0;
+    for (var i = 0, j = 0; i < str.length; i++) {
+        var bits = vlq_bits[str[i]];
+        value += (bits & 31) << shift;
+        if (bits & 32) {
+            shift += 5;
+        } else {
+            indices[j++] += value & 1 ? 0x80000000 | -(value >> 1) : value >> 1;
+            value = shift = 0;
+        }
+    }
+    return j;
+}
+
+function vlq_encode(num) {
+    var result = "";
+    num = Math.abs(num) << 1 | num >>> 31;
+    do {
+        var bits = num & 31;
+        if (num >>>= 5) bits |= 32;
+        result += vlq_char[bits];
+    } while (num);
+    return result;
+}
+
+function create_array_map() {
+    var map = Object.create(null);
+    var array = [];
+    array.index = function(name) {
+        if (!HOP(map, name)) {
+            map[name] = array.length;
+            array.push(name);
+        }
+        return map[name];
+    };
+    return array;
+}
+
 function SourceMap(options) {
     options = defaults(options, {
+        content: false,
         file: null,
         root: null,
         orig: null,
-        orig_line_diff: 0,
-        dest_line_diff: 0,
     }, true);
-    var generator = new MOZ_SourceMap.SourceMapGenerator({
-        file: options.file,
-        sourceRoot: options.root
-    });
-    var maps = options.orig && Object.create(null);
-    if (maps) for (var source in options.orig) {
-        var map = new MOZ_SourceMap.SourceMapConsumer(options.orig[source]);
-        if (Array.isArray(options.orig[source].sources)) {
-            map._sources.toArray().forEach(function(source) {
-                var sourceContent = map.sourceContentFor(source, true);
-                if (sourceContent) generator.setSourceContent(source, sourceContent);
+    var sources = create_array_map();
+    var sources_content = options.content && Object.create(null);
+    var names = create_array_map();
+    var mappings = "";
+    if (options.orig) Object.keys(options.orig).forEach(function(name) {
+        var map = options.orig[name];
+        var indices = [ 0, 0, 1, 0, 0 ];
+        map.mappings = map.mappings.split(/;/).map(function(line) {
+            indices[0] = 0;
+            return line.split(/,/).map(function(segment) {
+                return indices.slice(0, vlq_decode(indices, segment));
             });
+        });
+        if (!sources_content || !map.sourcesContent) return;
+        for (var i = 0; i < map.sources.length; i++) {
+            var content = map.sourcesContent[i];
+            if (content) sources_content[map.sources[i]] = content;
         }
-        maps[source] = map;
-    }
+    });
+    var generated_line = 1;
+    var generated_column = 0;
+    var source_index = 0;
+    var original_line = 1;
+    var original_column = 0;
+    var name_index = 0;
     return {
-        add: function(source, gen_line, gen_col, orig_line, orig_col, name) {
-            var map = maps && maps[source];
+        add: options.orig ? function(source, gen_line, gen_col, orig_line, orig_col, name) {
+            var map = options.orig[source];
             if (map) {
-                var info = map.originalPositionFor({
-                    line: orig_line,
-                    column: orig_col
-                });
-                if (info.source === null) return;
-                source = info.source;
-                orig_line = info.line;
-                orig_col = info.column;
-                name = info.name || name;
-            }
-            generator.addMapping({
-                name: name,
-                source: source,
-                generated: {
-                    line: gen_line + options.dest_line_diff,
-                    column: gen_col
-                },
-                original: {
-                    line: orig_line + options.orig_line_diff,
-                    column: orig_col
+                var segments = map.mappings[orig_line - 1];
+                if (!segments) return;
+                var indices;
+                for (var i = 0; i < segments.length; i++) {
+                    var col = segments[i][0];
+                    if (orig_col >= col) indices = segments[i];
+                    if (orig_col <= col) break;
                 }
-            });
-        },
-        get: function() {
-            return generator;
-        },
+                if (!indices) return;
+                source = map.sources[indices[1]];
+                orig_line = indices[2];
+                orig_col = indices[3];
+                if (indices.length > 4) name = map.names[indices[4]];
+            }
+            add(source, gen_line, gen_col, orig_line, orig_col, name);
+        } : add,
+        setSourceContent: sources_content ? function(source, content) {
+            sources_content[source] = content;
+        } : noop,
         toString: function() {
-            return JSON.stringify(generator.toJSON());
+            return JSON.stringify({
+                version: 3,
+                file: options.file || undefined,
+                sourceRoot: options.root || undefined,
+                sources: sources,
+                sourcesContent: sources_content ? sources.map(function(source) {
+                    return sources_content[source] || null;
+                }) : undefined,
+                names: names,
+                mappings: mappings,
+            });
         }
     };
+
+    function add(source, gen_line, gen_col, orig_line, orig_col, name) {
+        if (generated_line < gen_line) {
+            generated_column = 0;
+            do {
+                mappings += ";";
+            } while (++generated_line < gen_line);
+        } else if (mappings) {
+            mappings += ",";
+        }
+        mappings += vlq_encode(gen_col - generated_column);
+        generated_column = gen_col;
+        var src_idx = sources.index(source);
+        mappings += vlq_encode(src_idx - source_index);
+        source_index = src_idx;
+        mappings += vlq_encode(orig_line - original_line);
+        original_line = orig_line;
+        mappings += vlq_encode(orig_col - original_column);
+        original_column = orig_col;
+        if (name != null) {
+            var name_idx = names.index(name);
+            mappings += vlq_encode(name_idx - name_index);
+            name_index = name_idx;
+        }
+    }
 }
diff --git a/package.json b/package.json
index d4e4d74b..463afcf5 100644
--- a/package.json
+++ b/package.json
@@ -23,8 +23,7 @@
     "LICENSE"
   ],
   "dependencies": {
-    "commander": "~2.20.3",
-    "source-map": "~0.6.1"
+    "commander": "~2.20.3"
   },
   "devDependencies": {
     "acorn": "~7.1.0",
diff --git a/test/exports.js b/test/exports.js
index 1274ec6e..fd1237f3 100644
--- a/test/exports.js
+++ b/test/exports.js
@@ -13,3 +13,4 @@ exports["to_ascii"] = to_ascii;
 exports["tokenizer"] = tokenizer;
 exports["TreeTransformer"] = TreeTransformer;
 exports["TreeWalker"] = TreeWalker;
+exports["vlq_decode"] = vlq_decode;
diff --git a/test/input/issue-3040/expect.js b/test/input/issue-3040/expect.js
index b911f3f8..199da039 100644
--- a/test/input/issue-3040/expect.js
+++ b/test/input/issue-3040/expect.js
@@ -1,2 +1,2 @@
 function _toConsumableArray(arr){if(Array.isArray(arr)){for(var i=0,arr2=Array(arr.length);i<arr.length;i++){arr2[i]=arr[i]}return arr2}else{return Array.from(arr)}}var _require=require("bar"),foo=_require.foo;var _require2=require("world"),hello=_require2.hello;foo.x.apply(foo,_toConsumableArray(foo.y(hello.z)));
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImlucHV0Mi5qcyJdLCJuYW1lcyI6WyJyZXF1aXJlIiwiYXJyIl0sIm1hcHBpbmdzIjoiMEpBQWNBLEtBQVFDIiwic291cmNlc0NvbnRlbnQiOlsiY29uc3Qge2Zvb30gPSByZXF1aXJlKFwiYmFyXCIpO1xuY29uc3Qge2hlbGxvfSA9IHJlcXVpcmUoXCJ3b3JsZFwiKTtcblxuZm9vLngoLi4uZm9vLnkoaGVsbG8ueikpO1xuIl19
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImlucHV0Mi5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyJjb25zdCB7Zm9vfSA9IHJlcXVpcmUoXCJiYXJcIik7XG5jb25zdCB7aGVsbG99ID0gcmVxdWlyZShcIndvcmxkXCIpO1xuXG5mb28ueCguLi5mb28ueShoZWxsby56KSk7XG4iXSwibmFtZXMiOlsicmVxdWlyZSIsImFyciJdLCJtYXBwaW5ncyI6IjBKQUFjQSxLQUFRQyJ9
diff --git a/test/input/issue-3294/output.js b/test/input/issue-3294/output.js
index f6d13804..33efadb6 100644
--- a/test/input/issue-3294/output.js
+++ b/test/input/issue-3294/output.js
@@ -1,2 +1,2 @@
 new function(){console.log(3)};
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSIsInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl19
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSJ9
diff --git a/test/input/issue-520/output.js b/test/input/issue-520/output.js
index f6d13804..33efadb6 100644
--- a/test/input/issue-520/output.js
+++ b/test/input/issue-520/output.js
@@ -1,2 +1,2 @@
 new function(){console.log(3)};
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSIsInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl19
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIl0sInNvdXJjZXNDb250ZW50IjpbImNsYXNzIEZvbyB7IGNvbnN0cnVjdG9yKCl7Y29uc29sZS5sb2coMSsyKTt9IH0gbmV3IEZvbygpO1xuIl0sIm5hbWVzIjpbImNvbnNvbGUiLCJsb2ciXSwibWFwcGluZ3MiOiJBQUErQyxJQUFyQyxXQUFnQkEsUUFBUUMsSUFBSSJ9
diff --git a/test/mocha/cli.js b/test/mocha/cli.js
index be7e9d23..0347797e 100644
--- a/test/mocha/cli.js
+++ b/test/mocha/cli.js
@@ -245,7 +245,7 @@ describe("bin/uglifyjs", function() {
             if (err) throw err;
             assert.strictEqual(stdout, [
                 "var Foo=function Foo(){console.log(1+2)};new Foo;var bar=function(){function foo(bar){return bar}return foo}();",
-                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwidGVzdC9pbnB1dC9pc3N1ZS0xMzIzL3NhbXBsZS5qcyJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFNBQUFBLE1BQWdCQyxRQUFRQyxJQUFJLEVBQUUsSUFBTyxJQUFJRixJQ0FuRCxJQUFJRyxJQUFNLFdBQ04sU0FBU0MsSUFBS0QsS0FDVixPQUFPQSxJQUdYLE9BQU9DLElBTEQifQ==",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbInN0ZGluIiwidGVzdC9pbnB1dC9pc3N1ZS0xMzIzL3NhbXBsZS5qcyJdLCJuYW1lcyI6WyJGb28iLCJjb25zb2xlIiwibG9nIiwiYmFyIiwiZm9vIl0sIm1hcHBpbmdzIjoiQUFBQSxJQUFNQSxJQUFJLFNBQUVBLE1BQWNDLFFBQVFDLElBQUksRUFBRSxJQUFPLElBQUlGLElDQW5ELElBQUlHLElBQU0sV0FDTixTQUFTQyxJQUFLRCxLQUNWLE9BQU9BLElBR1gsT0FBT0MsSUFMRCJ9",
                 "",
             ].join("\n"));
             var stderrLines = stderr.split("\n");
@@ -587,7 +587,7 @@ describe("bin/uglifyjs", function() {
         });
 
         function read_map() {
-            var map = JSON.parse(read("./test/input/issue-1236/simple.js.map"));
+            var map = JSON.parse(read("test/input/issue-1236/simple.js.map"));
             delete map.sourcesContent;
             return JSON.stringify(map).replace(/"/g, '\\"');
         }
diff --git a/test/mocha/sourcemaps.js b/test/mocha/sourcemaps.js
index 7b1c70ff..f8e399ce 100644
--- a/test/mocha/sourcemaps.js
+++ b/test/mocha/sourcemaps.js
@@ -1,10 +1,9 @@
 var assert = require("assert");
-var readFileSync = require("fs").readFileSync;
-var SourceMapConsumer = require("source-map").SourceMapConsumer;
+var fs = require("fs");
 var UglifyJS = require("../node");
 
 function read(path) {
-    return readFileSync(path, "utf8");
+    return fs.readFileSync(path, "utf8");
 }
 
 function source_map(code) {
@@ -44,7 +43,7 @@ function prepare_map(sourceMap) {
         }
     });
     if (result.error) throw result.error;
-    return new SourceMapConsumer(result.map);
+    return JSON.parse(result.map);
 }
 
 describe("sourcemaps", function() {
@@ -87,7 +86,7 @@ describe("sourcemaps", function() {
         });
         if (result.error) throw result.error;
         assert.strictEqual(result.code, code);
-        assert.strictEqual(result.map, '{"version":3,"sources":["0"],"names":["console","log"],"mappings":"AAAAA,QAAQC,IAAI","sourceRoot":"//foo.bar/"}');
+        assert.strictEqual(result.map, '{"version":3,"sourceRoot":"//foo.bar/","sources":["0"],"names":["console","log"],"mappings":"AAAAA,QAAQC,IAAI"}');
     });
     it("Should produce same source map with DOS or UNIX line endings", function() {
         var code = [
@@ -108,9 +107,9 @@ describe("sourcemaps", function() {
 
     describe("inSourceMap", function() {
         it("Should read the given string filename correctly when sourceMapIncludeSources is enabled", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-1236/simple.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-1236/simple.js"), {
                 sourceMap: {
-                    content: read("./test/input/issue-1236/simple.js.map"),
+                    content: read("test/input/issue-1236/simple.js.map"),
                     filename: "simple.min.js",
                     includeSources: true
                 }
@@ -122,7 +121,7 @@ describe("sourcemaps", function() {
             assert.equal(map.sourcesContent[0], 'let foo = x => "foo " + x;\nconsole.log(foo("bar"));');
         });
         it("Should process inline source map", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-520/input.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-520/input.js"), {
                 compress: { toplevel: true },
                 sourceMap: {
                     content: "inline",
@@ -131,10 +130,10 @@ describe("sourcemaps", function() {
                 }
             });
             if (result.error) throw result.error;
-            assert.strictEqual(result.code + "\n", readFileSync("test/input/issue-520/output.js", "utf8"));
+            assert.strictEqual(result.code + "\n", read("test/input/issue-520/output.js"));
         });
         it("Should warn for missing inline source map", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-1323/sample.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-1323/sample.js"), {
                 mangle: false,
                 sourceMap: {
                     content: "inline"
@@ -146,8 +145,8 @@ describe("sourcemaps", function() {
         });
         it("Should handle multiple input and inline source map", function() {
             var result = UglifyJS.minify([
-                read("./test/input/issue-520/input.js"),
-                read("./test/input/issue-1323/sample.js"),
+                read("test/input/issue-520/input.js"),
+                read("test/input/issue-1323/sample.js"),
             ], {
                 sourceMap: {
                     content: "inline",
@@ -163,7 +162,7 @@ describe("sourcemaps", function() {
             assert.deepEqual(result.warnings, [ "WARN: inline source map not found: 1" ]);
         });
         it("Should drop source contents for includeSources=false", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-520/input.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-520/input.js"), {
                 compress: false,
                 mangle: false,
                 sourceMap: {
@@ -186,7 +185,7 @@ describe("sourcemaps", function() {
             assert.ok(!("sourcesContent" in map));
         });
         it("Should parse the correct sourceMappingURL", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-3294/input.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-3294/input.js"), {
                 compress: { toplevel: true },
                 sourceMap: {
                     content: "inline",
@@ -195,10 +194,10 @@ describe("sourcemaps", function() {
                 }
             });
             if (result.error) throw result.error;
-            assert.strictEqual(result.code + "\n", readFileSync("test/input/issue-3294/output.js", "utf8"));
+            assert.strictEqual(result.code + "\n", read("test/input/issue-3294/output.js"));
         });
         it("Should work in presence of unrecognised annotations", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-3441/input.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-3441/input.js"), {
                 compress: false,
                 mangle: false,
                 sourceMap: {
@@ -230,7 +229,7 @@ describe("sourcemaps", function() {
             assert.strictEqual(code, "var a=function(n){return n};");
         });
         it("Should work with max_line_len", function() {
-            var result = UglifyJS.minify(read("./test/input/issue-505/input.js"), {
+            var result = UglifyJS.minify(read("test/input/issue-505/input.js"), {
                 compress: {
                     directives: false,
                 },
@@ -242,7 +241,7 @@ describe("sourcemaps", function() {
                 }
             });
             if (result.error) throw result.error;
-            assert.strictEqual(result.code, read("./test/input/issue-505/output.js"));
+            assert.strictEqual(result.code, read("test/input/issue-505/output.js"));
         });
         it("Should work with unicode characters", function() {
             var code = [
@@ -281,29 +280,33 @@ describe("sourcemaps", function() {
         it("Should copy over original sourcesContent", function() {
             var orig = get_map();
             var map = prepare_map(orig);
-            assert.equal(map.sourceContentFor("index.js"), orig.sourcesContent[0]);
+            assert.strictEqual(map.sources.length, 1);
+            assert.strictEqual(map.sources[0], "index.js");
+            assert.strictEqual(map.sourcesContent.length, 1);
+            assert.equal(map.sourcesContent[0], orig.sourcesContent[0]);
         });
         it("Should copy sourcesContent if sources are relative", function() {
             var relativeMap = get_map();
             relativeMap.sources = ['./index.js'];
             var map = prepare_map(relativeMap);
-            assert.notEqual(map.sourcesContent, null);
-            assert.equal(map.sourcesContent.length, 1);
-            assert.equal(map.sourceContentFor("index.js"), relativeMap.sourcesContent[0]);
+            assert.strictEqual(map.sources.length, 1);
+            assert.strictEqual(map.sources[0], "./index.js");
+            assert.strictEqual(map.sourcesContent.length, 1);
+            assert.equal(map.sourcesContent[0], relativeMap.sourcesContent[0]);
         });
         it("Should not have invalid mappings from inputSourceMap", function() {
             var map = prepare_map(get_map());
             // The original source has only 2 lines, check that mappings don't have more lines
             var msg = "Mapping should not have higher line number than the original file had";
-            map.eachMapping(function(mapping) {
-                assert.ok(mapping.originalLine <= 2, msg);
-            });
-            map.allGeneratedPositionsFor({
-                source: "index.js",
-                line: 1,
-                column: 1
-            }).forEach(function(pos) {
-                assert.ok(pos.line <= 2, msg);
+            var lines = map.mappings.split(/;/);
+            assert.ok(lines.length <= 2, msg);
+            var indices = [ 0, 0, 1, 0, 0];
+            lines.forEach(function(segments) {
+                indices[0] = 0;
+                segments.split(/,/).forEach(function(segment) {
+                    UglifyJS.vlq_decode(indices, segment);
+                    assert.ok(indices[2] <= 2, msg);
+                });
             });
         });
     });
diff --git a/test/node.js b/test/node.js
index 22bf325d..fc3a14dc 100644
--- a/test/node.js
+++ b/test/node.js
@@ -1,6 +1,6 @@
 var fs = require("fs");
 
-new Function("MOZ_SourceMap", "exports", require("../tools/node").FILES.map(function(file) {
+new Function("exports", require("../tools/node").FILES.map(function(file) {
     if (/exports\.js$/.test(file)) file = require.resolve("./exports");
     return fs.readFileSync(file, "utf8");
-}).join("\n\n"))(require("source-map"), exports);
+}).join("\n\n"))(exports);
diff --git a/tools/node.js b/tools/node.js
index 58150e6b..ef05f571 100644
--- a/tools/node.js
+++ b/tools/node.js
@@ -15,13 +15,13 @@ exports.FILES = [
     require.resolve("./exports.js"),
 ];
 
-new Function("MOZ_SourceMap", "exports", function() {
+new Function("exports", function() {
     var code = exports.FILES.map(function(file) {
         return fs.readFileSync(file, "utf8");
     });
     code.push("exports.describe_ast = " + describe_ast.toString());
     return code.join("\n\n");
-}())(require("source-map"), exports);
+}())(exports);
 
 function describe_ast() {
     var out = OutputStream({ beautify: true });