Support trees with immediate .start and .end (without .range)

.travis.yml

@@ -1,6 +1,6 @@
 sudo: false
 language: node_js
 node_js:
-  - "4"
-  - "6"
   - "8"
+  - "10"
+  - "12"

escodegen.js

@@ -79,6 +79,14 @@
         return CodeGenerator.Statement.hasOwnProperty(node.type);
     }
 
+    // Get range either by directly accessing .start + .end or accessing .range
+    function getRange(node) {
+        if (!("range" in node)) {
+            return [node.start, node.end];
+        }
+        return node.range;
+    }
+
     Precedence = {
         Sequence: 0,
         Yield: 1,
@@ -668,7 +676,7 @@
                 result = [];
 
                 extRange = comment.extendedRange;
-                range = comment.range;
+                range = getRange(comment);
 
                 prefix = sourceCode.substring(extRange[0], range[0]);
                 count = (prefix.match(/\n/g) || []).length;
@@ -684,7 +692,7 @@
 
                 for (i = 1, len = stmt.leadingComments.length; i < len; i++) {
                     comment = stmt.leadingComments[i];
-                    range = comment.range;
+                    range = getRange(comment);
 
                     infix = sourceCode.substring(prevRange[1], range[0]);
                     count = (infix.match(/\n/g) || []).length;
@@ -726,7 +734,7 @@
             if (preserveBlankLines) {
                 comment = stmt.trailingComments[0];
                 extRange = comment.extendedRange;
-                range = comment.range;
+                range = getRange(comment);
 
                 prefix = sourceCode.substring(extRange[0], range[0]);
                 count = (prefix.match(/\n/g) || []).length;
@@ -1023,7 +1031,7 @@
             withIndent(function () {
                 // handle functions without any code
                 if (stmt.body.length === 0 && preserveBlankLines) {
-                    range = stmt.range;
+                    range = getRange(stmt);
                     if (range[1] - range[0] > 2) {
                         content = sourceCode.substring(range[0] + 1, range[1] - 1);
                         if (content[0] === '\n') {
@@ -1051,14 +1059,14 @@
                                 }
                             }
                             if (!stmt.body[0].leadingComments) {
-                                generateBlankLines(stmt.range[0], stmt.body[0].range[0], result);
+                                generateBlankLines(getRange(stmt)[0], getRange(stmt.body[0])[0], result);
                             }
                         }
 
                         // handle spaces between lines
                         if (i > 0) {
                             if (!stmt.body[i - 1].trailingComments  && !stmt.body[i].leadingComments) {
-                                generateBlankLines(stmt.body[i - 1].range[1], stmt.body[i].range[0], result);
+                                generateBlankLines(getRange(stmt.body[i - 1])[1], getRange(stmt.body[i])[0], result);
                             }
                         }
                     }
@@ -1090,7 +1098,7 @@
                         // handle spaces after the last line
                         if (i === iz - 1) {
                             if (!stmt.body[i].trailingComments) {
-                                generateBlankLines(stmt.body[i].range[1], stmt.range[1], result);
+                                generateBlankLines(getRange(stmt.body[i])[1], getRange(stmt)[1], result);
                             }
                         }
                     }
@@ -1692,14 +1700,14 @@
                     // handle spaces before the first line
                     if (i === 0) {
                         if (!stmt.body[0].leadingComments) {
-                            generateBlankLines(stmt.range[0], stmt.body[i].range[0], result);
+                            generateBlankLines(getRange(stmt)[0], getRange(stmt.body[i])[0], result);
                         }
                     }
 
                     // handle spaces between lines
                     if (i > 0) {
                         if (!stmt.body[i - 1].trailingComments && !stmt.body[i].leadingComments) {
-                            generateBlankLines(stmt.body[i - 1].range[1], stmt.body[i].range[0], result);
+                            generateBlankLines(getRange(stmt.body[i - 1])[1], getRange(stmt.body[i])[0], result);
                         }
                     }
                 }
@@ -1720,7 +1728,7 @@
                     // handle spaces after the last line
                     if (i === iz - 1) {
                         if (!stmt.body[i].trailingComments) {
-                            generateBlankLines(stmt.body[i].range[1], stmt.range[1], result);
+                            generateBlankLines(getRange(stmt.body[i])[1], getRange(stmt)[1], result);
                         }
                     }
                 }

gulpfile.js

@@ -79,5 +79,5 @@ gulp.task('lint', function () {
         .pipe(eslint.failOnError());
 });
 
-gulp.task('travis', [ 'lint', 'test' ]);
-gulp.task('default', [ 'travis' ]);
+gulp.task('travis', gulp.parallel('lint', 'test'));
+gulp.task('default', gulp.parallel('travis'));

package.json

@@ -44,9 +44,9 @@
         "bower-registry-client": "^1.0.0",
         "chai": "^3.5.0",
         "commonjs-everywhere": "^0.9.7",
-        "gulp": "^3.8.10",
-        "gulp-eslint": "^3.0.1",
-        "gulp-mocha": "^3.0.1",
+        "gulp": "^4.0.1",
+        "gulp-eslint": "^6.0.0",
+        "gulp-mocha": "^7.0.2",
         "semver": "^5.1.0"
     },
     "license": "BSD-2-Clause",

test/compare-acorn-preserve-blank-lines.js

@@ -0,0 +1,66 @@
+/*
+  Copyright (C) 2019 Guy Lewin <guy@lewin.co.il>
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+  ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
+  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+'use strict';
+
+var fs = require('fs'),
+    acorn = require('acorn'),
+    escodegen = require('./loader'),
+    chai = require('chai'),
+    expect = chai.expect;
+
+function test(code, expected) {
+    var tree, actual, options, StringObject;
+
+    // alias, so that JSLint does not complain.
+    StringObject = String;
+
+    tree = acorn.parse(code);
+
+    options = {
+        sourceCode: code,
+        format: {
+            preserveBlankLines: true
+        }
+    }
+
+    // for UNIX text comment
+    actual = escodegen.generate(tree, options).replace(/[\n\r]$/, '') + '\n';
+    expect(actual).to.be.equal(expected);
+}
+
+describe('compare acorn preserve blank lines test', function () {
+    fs.readdirSync(__dirname + '/compare-acorn-preserve-blank-lines').sort().forEach(function(file) {
+        var code, expected, exp;
+        if (/\.js$/.test(file) && !/expected\.js$/.test(file)) {
+            it(file, function () {
+                exp = file.replace(/\.js$/, '.expected.js');
+                code = fs.readFileSync(__dirname + '/compare-acorn-preserve-blank-lines/' + file, 'utf-8');
+                expected = fs.readFileSync(__dirname + '/compare-acorn-preserve-blank-lines/' + exp, 'utf-8');
+                test(code, expected);
+            });
+        }
+    });
+});
+/* vim: set sw=4 ts=4 et tw=80 : */

test/compare-acorn-preserve-blank-lines/block-statement.expected.js

@@ -0,0 +1,2 @@
+{
+     }

test/compare-acorn-preserve-blank-lines/block-statement.js

@@ -0,0 +1,2 @@
+{
+     }

test/range.js

@@ -0,0 +1,85 @@
+/*
+ Copyright (C) 2019 Guy Lewin <guy@lewin.co.il>
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+'use strict';
+
+var fs = require('fs'),
+    esprima = require('esprima'),
+    escodegen = require('./loader'),
+    chai = require('chai'),
+    expect = chai.expect;
+
+function test(tree) {
+    var tree, actual;
+    var code = "{\n    }";
+    var options = {
+        sourceCode: code,
+        format: {
+            preserveBlankLines: true
+        }
+    };
+
+    actual = escodegen.generate(tree, options);
+    expect(actual).to.be.equal(code);
+}
+
+describe('test building trees with and without range', function () {
+    it("with range - Esprima built", function () {
+        // Parsed by Esprima
+        test({
+            "type": "Program",
+            "body": [{
+                "type": "BlockStatement",
+                "body": [],
+                "range": [
+                    0,
+                    7
+                ]
+            }],
+            "sourceType": "module",
+            "range": [
+                0,
+                7
+            ]
+        });
+    });
+
+    it("without range - Acorn built", function () {
+        // Parsed by Acorn
+        test({
+            "type": "Program",
+            "start": 0,
+            "end": 7,
+            "body": [{
+                "type": "BlockStatement",
+                "start": 0,
+                "end": 7,
+                "body": []
+            }],
+            "sourceType": "module"
+        });
+    });
+});
+
+/* vim: set sw=4 ts=4 et tw=80 : */