Add print-script helper script

1 files changed, 95 insertions, 0 deletions

diff --git a/print-script b/print-script
new file mode 100755
index 0000000..046b99c
--- /dev/null
+++ b/print-script
@@ -0,0 +1,95 @@
+#! /usr/bin/env node
+/* eslint-disable no-console, no-var */
+// Util script for debugging source code generation issues
+
+var script = process.argv[2].replace(/\\n/g, '\n'),
+    verbose = process.argv[3] === '-v';
+
+var Handlebars = require('./lib'),
+    SourceMap = require('source-map'),
+      SourceMapConsumer = SourceMap.SourceMapConsumer;
+
+var template = Handlebars.precompile(script, {
+      srcName: 'input.hbs',
+      destName: 'output.js',
+
+      assumeObjects: true,
+      compat: false,
+      strict: true,
+      trackIds: true,
+      knownHelpersOnly: false
+    });
+
+if (!verbose) {
+  console.log(template);
+} else {
+  var consumer = new SourceMapConsumer(template.map),
+      lines = template.code.split('\n'),
+      srcLines = script.split('\n');
+
+  console.log();
+  console.log('Source:');
+  srcLines.forEach(function(source, index) {
+    console.log(index + 1, source);
+  });
+  console.log();
+  console.log('Generated:');
+  console.log(template.code);
+  lines.forEach(function(source, index) {
+    console.log(index + 1, source);
+  });
+  console.log();
+  console.log('Map:');
+  console.log(template.map);
+  console.log();
+
+  function collectSource(lines, lineName, colName, order) {
+    var ret = {},
+        ordered = [],
+        last;
+
+    function collect(current) {
+      if (last) {
+        var mapLines = lines.slice(last[lineName] - 1, current && current[lineName]);
+        if (mapLines.length) {
+          if (current) {
+            mapLines[mapLines.length - 1] = mapLines[mapLines.length - 1].slice(0, current[colName]);
+          }
+          mapLines[0] = mapLines[0].slice(last[colName]);
+        }
+        ret[last[lineName] + ':' + last[colName]] = mapLines.join('\n');
+        ordered.push({
+          startLine: last[lineName],
+          startCol: last[colName],
+          endLine: current && current[lineName]
+        });
+      }
+      last = current;
+    }
+
+    consumer.eachMapping(collect, undefined, order);
+    collect();
+
+    return ret;
+  }
+
+  srcLines = collectSource(srcLines, 'originalLine', 'originalColumn', SourceMapConsumer.ORIGINAL_ORDER);
+  lines = collectSource(lines, 'generatedLine', 'generatedColumn');
+
+  consumer.eachMapping(function(mapping) {
+    var originalSrc = srcLines[mapping.originalLine + ':' + mapping.originalColumn],
+        generatedSrc = lines[mapping.generatedLine + ':' + mapping.generatedColumn];
+
+    if (!mapping.originalLine) {
+      console.log('generated', mapping.generatedLine + ':' + mapping.generatedColumn, generatedSrc);
+    } else {
+      console.log('map',
+          mapping.source,
+          mapping.originalLine + ':' + mapping.originalColumn,
+          originalSrc,
+          '->',
+          mapping.generatedLine + ':' + mapping.generatedColumn,
+          generatedSrc);
+    }
+  });
+}