First Commit

html/sternwarte/checkfuehrung/node_modules/redeyed/examples/replace-log.js

@@ -0,0 +1,58 @@
+var path    =  require('path')
+var fs      =  require('fs')
+var redeyed =  require('..')
+var vm      =  require('vm')
+
+var samplePath =  path.join(__dirname, 'sources', 'log.js')
+var origCode   =  fs.readFileSync(samplePath, 'utf-8')
+var kinds = [ 'silly', 'info', 'warn', 'error' ]
+
+function replaceConsole(s, info) {
+  var code        =  info.code
+  var idx         =  info.tokenIndex
+  var tokens      =  info.tokens
+  var next        =  tokens[idx + 1].value
+  var kind        =  tokens[idx + 2].value
+  var openParen   =  tokens[idx + 3].value
+  var firstArgTkn =  tokens[idx + 4]
+  var argIdx      =  idx + 3
+  var open
+  var tkn
+
+  if (kind === 'log') kind = 'silly'
+
+  // not a console.xxx(...) statement? -> just return original
+  if (next !== '.' || !~kinds.indexOf(kind) || openParen !== '(') return s
+
+  // skip past arguments to console.xxx all args from ( to )
+  open = 1
+  while (open) {
+    tkn = tokens[++argIdx]
+
+    // count open parens vs. closed ones to handle things like console.log(new Error('..'));
+    if (tkn.value === '(') open++
+    if (tkn.value === ')') open--
+  }
+
+  // tkn now is the last closing paren
+  var argsIncludingClosingParen =  code.slice(firstArgTkn.range[0], tkn.range[1])
+  var result                    =  'log.' + kind + '("main-logger", ' + argsIncludingClosingParen
+
+  // tell redeyed to skip the entire console.xxx(..) statement since we are replacing it all
+  return { replacement: result, skipPastToken: tkn }
+}
+
+function transformAndRun() {
+  var config = {
+        Identifier: { console: replaceConsole }
+      }
+  var code        =  redeyed(origCode, config).code
+  var context     =  vm.createContext({ require: require })
+
+  console.log('Original code:\n', origCode)
+  console.log('\nlog calls replaced:\n', code)
+  console.log('\nLets run it:')
+  vm.runInContext(code, context, 'transformed-log.vm')
+}
+
+transformAndRun()