add extended variable checking

ts/smarthbs.variables.ts

@@ -0,0 +1,61 @@
+// This file contains code that makes it easy to search handlebar templates for variables.
+// Why? To get a clue if you are missing some.
+
+import * as plugins from './smarthbs.plugins'
+
+// the curly regex objects
+let tripleCurlyRegex = /{{{\s*[\w\.]+\s*}}}/g
+let doubleCurlyRegex = /{{\s*[\w\.]+\s*}}/g
+let nameInCurlsRegex = /[\w\.]+/
+
+/**
+ * finds all variables in a handlebars template
+ * @param hbsStringArg
+ */
+export let findVarsInHbsString = async (hbsStringArg: string) => {
+  let hbsString = hbsStringArg // make sure we have a new string object that we may destroy
+  let varNameArray: string[] = []
+  let tripleCurlyMatches = hbsString.match(tripleCurlyRegex)
+  hbsString = hbsString.replace(tripleCurlyRegex, '[[[replaced]]]')
+  let doubleCurlyMatches = hbsString.match(doubleCurlyRegex)
+  hbsString = hbsString.replace(doubleCurlyRegex, '[[[replaced]]]')
+  varNameArray = plugins.lodash.concat(varNameArray, tripleCurlyMatches, doubleCurlyMatches)
+    .map((x) => {
+      return x.match(nameInCurlsRegex)[ 0 ]
+    })
+  varNameArray = plugins.lodash.uniq(varNameArray)
+  return varNameArray
+}
+
+/**
+ * checks if supplied variables satisfy an handlebars template
+ * @param hbsStringArg
+ * @param varObjectArg 
+ */
+export let checkVarsSatisfaction = async (hbsStringArg: string, varObjectArg: any) => {
+  // required vars as combined deep string with . notation
+  let requiredVarStrings = await findVarsInHbsString(hbsStringArg)
+
+  // comparison objects
+  let suppliedVarsObject = varObjectArg
+  let missingVarsObject: string[] = []
+
+  // building the 
+  for (let stringVar of requiredVarStrings) {
+    let splittedVars = stringVar.split('.')
+    let requiredPointer = suppliedVarsObject
+    for (let i = 0; i < splittedVars.length; i++) {
+      let splitVar = splittedVars[i]
+      let varAvailable = (requiredPointer[splitVar] !== undefined)
+      if (varAvailable && splittedVars.length === (i + 1)) {
+        // ok
+      } else if (varAvailable) {
+        requiredPointer = requiredPointer[splitVar]
+      } else {
+        missingVarsObject.push(stringVar)
+        i = splittedVars.length
+      }
+    }
+  }
+  return missingVarsObject
+}