improve source-map generation (#3782)

- emit singleton segments to mark generated code from input

7 files changed, 84 insertions, 15 deletions

diff --git a/lib/output.js b/lib/output.js
index f05c93df..31c7a4b4 100644
--- a/lib/output.js
+++ b/lib/output.js
@@ -1470,7 +1470,6 @@ function OutputStream(options) {
         AST_Node,
         // since the label symbol will mark it
         AST_LabeledStatement,
-        AST_Toplevel,
     ], noop);
 
     // XXX: I'm not exactly sure if we need it for all of these nodes,
@@ -1482,7 +1481,6 @@ function OutputStream(options) {
         AST_Constant,
         AST_Debugger,
         AST_Definitions,
-        AST_Directive,
         AST_Finally,
         AST_Jump,
         AST_Lambda,
diff --git a/lib/sourcemap.js b/lib/sourcemap.js
index 25fbe3bf..fc200ced 100644
--- a/lib/sourcemap.js
+++ b/lib/sourcemap.js
@@ -119,6 +119,7 @@ function SourceMap(options) {
             if (content) sources_content[map.sources[i]] = content;
         }
     });
+    var prev_source;
     var generated_line = 1;
     var generated_column = 0;
     var source_index = 0;
@@ -137,11 +138,14 @@ function SourceMap(options) {
                     if (orig_col >= col) indices = segments[i];
                     if (orig_col <= col) break;
                 }
-                if (!indices || indices.length < 4) return;
-                source = map.sources[indices[1]];
-                orig_line = indices[2];
-                orig_col = indices[3];
-                if (indices.length > 4) name = map.names[indices[4]];
+                if (!indices || indices.length < 4) {
+                    source = null;
+                } else {
+                    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,
@@ -164,6 +168,8 @@ function SourceMap(options) {
     };
 
     function add(source, gen_line, gen_col, orig_line, orig_col, name) {
+        if (prev_source == null && source == null) return;
+        prev_source = source;
         if (generated_line < gen_line) {
             generated_column = 0;
             do {
@@ -174,6 +180,7 @@ function SourceMap(options) {
         }
         mappings += vlq_encode(gen_col - generated_column);
         generated_column = gen_col;
+        if (source == null) return;
         var src_idx = sources.index(source);
         mappings += vlq_encode(src_idx - source_index);
         source_index = src_idx;
diff --git a/test/input/issue-3040/expect.js b/test/input/issue-3040/expect.js
index 199da039..d207fcbe 100644
--- a/test/input/issue-3040/expect.js
+++ b/test/input/issue-3040/expect.js
@@ -1,2 +1,41 @@
-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,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImlucHV0Mi5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyJjb25zdCB7Zm9vfSA9IHJlcXVpcmUoXCJiYXJcIik7XG5jb25zdCB7aGVsbG99ID0gcmVxdWlyZShcIndvcmxkXCIpO1xuXG5mb28ueCguLi5mb28ueShoZWxsby56KSk7XG4iXSwibmFtZXMiOlsicmVxdWlyZSIsImFyciJdLCJtYXBwaW5ncyI6IjBKQUFjQSxLQUFRQyJ9
+"use strict";
+
+function _toConsumableArray(arr) {
+    return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread();
+}
+
+function _nonIterableSpread() {
+    throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
+}
+
+function _unsupportedIterableToArray(o, minLen) {
+    if (!o) return;
+    if (typeof o === "string") return _arrayLikeToArray(o, minLen);
+    var n = Object.prototype.toString.call(o).slice(8, -1);
+    if (n === "Object" && o.constructor) n = o.constructor.name;
+    if (n === "Map" || n === "Set") return Array.from(n);
+    if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen);
+}
+
+function _iterableToArray(iter) {
+    if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter);
+}
+
+function _arrayWithoutHoles(arr) {
+    if (Array.isArray(arr)) return _arrayLikeToArray(arr);
+}
+
+function _arrayLikeToArray(arr, len) {
+    if (len == null || len > arr.length) len = arr.length;
+    for (var i = 0, arr2 = new Array(len); i < len; i++) {
+        arr2[i] = arr[i];
+    }
+    return arr2;
+}
+
+var _require = require("bar"), foo = _require.foo;
+
+var _require2 = require("world"), hello = _require2.hello;
+
+foo.x.apply(foo, _toConsumableArray(foo.y(hello.z)));
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,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
diff --git a/test/input/issue-3040/input.js b/test/input/issue-3040/input.js
index 6515dcbd..6e4c2cce 100644
--- a/test/input/issue-3040/input.js
+++ b/test/input/issue-3040/input.js
@@ -1,4 +1,16 @@
-function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+"use strict";
+
+function _toConsumableArray(arr) { return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread(); }
+
+function _nonIterableSpread() { throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
+
+function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(n); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
+
+function _iterableToArray(iter) { if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter); }
+
+function _arrayWithoutHoles(arr) { if (Array.isArray(arr)) return _arrayLikeToArray(arr); }
+
+function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }
 
 var _require = require("bar"),
     foo = _require.foo;
diff --git a/test/input/issue-3040/input.js.map b/test/input/issue-3040/input.js.map
index f0883e22..ed37190a 100644
--- a/test/input/issue-3040/input.js.map
+++ b/test/input/issue-3040/input.js.map
@@ -1 +1,11 @@
-{"version":3,"sources":["input2.js"],"names":["require","foo","hello","x","apply","_toConsumableArray","y","z"],"mappings":"kLAAcA,QAAQ,OAAfC,aAAAA,kBACSD,QAAQ,SAAjBE,gBAAAA,MAEPD,IAAIE,EAAJC,MAAAH,IAAAI,mBAASJ,IAAIK,EAAEJ,MAAMK","sourcesContent":["const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"]}
\ No newline at end of file
+{

+    "version": 3,

+    "sources": [

+        "input.js"

+    ],

+    "names": [],

+    "mappings": ";;;;;;;;;;;;;;eAAc,OAAO,CAAC,KAAD,C;IAAd,G,YAAA,G;;gBACS,OAAO,CAAC,OAAD,C;IAAhB,K,aAAA,K;;AAEP,GAAG,CAAC,CAAJ,OAAA,GAAG,qBAAM,GAAG,CAAC,CAAJ,CAAM,KAAK,CAAC,CAAZ,CAAN,EAAH",

+    "sourcesContent": [

+        "const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"

+    ]

+}

diff --git a/test/input/issue-505/output.js b/test/input/issue-505/output.js
index fec88ee0..d81d0f92 100644
--- a/test/input/issue-505/output.js
+++ b/test/input/issue-505/output.js
@@ -2,4 +2,4 @@ function test(a){
 "aaaaaaaaaaaaaaaa"
 ;a(err,data),a(err,
 data)}
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7QUFDVjtDQUNBQSxFQUFTQyxJQUFLQyxNQUNkRixFQUFTQztBQUFLQyJ9
\ No newline at end of file
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7O0NBRVZBLEVBQVNDLElBQUtDLE1BQ2RGLEVBQVNDO0FBQUtDIn0=
\ No newline at end of file
diff --git a/test/mocha/cli.js b/test/mocha/cli.js
index 82f76c0d..8642a6b4 100644
--- a/test/mocha/cli.js
+++ b/test/mocha/cli.js
@@ -109,9 +109,12 @@ describe("bin/uglifyjs", function() {
         }
         var command = [
             uglifyjscmd,
-            "--source-map", "content=" + mapFile,
-            "--source-map", "includeSources=true",
-            "--source-map", "url=inline",
+            "--beautify",
+            "--source-map", [
+                "content=" + mapFile,
+                "includeSources",
+                "url=inline",
+            ].join(","),
         ].join(" ");
 
         var child = exec(command, function(err, stdout) {