Adding a manifest of all the useful helpers which our system provides.

packages/string-templates/package.json

@@ -20,6 +20,7 @@
   },
   "devDependencies": {
     "@rollup/plugin-json": "^4.1.0",
+    "doctrine": "^3.0.0",
     "jest": "^26.6.3",
     "rollup": "^2.36.2",
     "rollup-plugin-commonjs": "^10.1.0",

packages/string-templates/scripts/gen-collection-info.js

@@ -0,0 +1,143 @@
+const helpers = require("handlebars-helpers")
+const { HelperFunctionBuiltin } = require("../src/helpers/constants")
+const fs = require("fs")
+const doctrine = require("doctrine")
+
+const FILENAME = "../manifest.json"
+
+/**
+ * full list of supported helpers can be found here:
+ * https://github.com/helpers/handlebars-helpers
+ */
+
+const COLLECTIONS = [
+  "math",
+  "array",
+  "number",
+  "url",
+  "string",
+  "comparison",
+]
+
+const outputJSON = {}
+
+function fixSpecialCases(name, obj) {
+  const args = obj.args
+  if (name === "ifNth") {
+    args[0] = "a"
+    args[1] = "b"
+  }
+  if (name === "eachIndex") {
+    obj.description = "Iterates the array, listing an item and the index of it."
+  }
+  if (name === "toFloat") {
+    obj.description = "Convert input to a float."
+  }
+  if (name === "toInt") {
+    obj.description = "Convert input to an integer."
+  }
+  // add the date helper
+  obj
+  return obj
+}
+
+function lookForward(lines, funcLines, idx) {
+  const funcLen = funcLines.length
+  for (let i = idx, j = 0; i < idx + funcLen; ++i, j++) {
+    if (!lines[i].includes(funcLines[j])) {
+      return false
+    }
+  }
+  return true
+}
+
+function getCommentInfo(file, func) {
+  const lines = file.split("\n")
+  const funcLines = func.split("\n")
+  let comment = null
+  for (let idx = 0; idx < lines.length; ++idx) {
+    // from here work back until we have the comment
+    if (lookForward(lines, funcLines, idx)) {
+      let fromIdx = idx
+      let start = 0, end = 0
+      do {
+        if (lines[fromIdx].includes("*/")) {
+          end = fromIdx
+        } else if (lines[fromIdx].includes("/*")) {
+          start = fromIdx
+        }
+        if (start && end) {
+          break
+        }
+        fromIdx--
+      } while (fromIdx > 0)
+      comment = lines.slice(start, end + 1).join("\n")
+    }
+  }
+  if (comment == null) {
+    return { description: "" }
+  }
+  const docs = doctrine.parse(comment, { unwrap: true })
+  // some hacky fixes
+  docs.description = docs.description.replace(/\n/g, " ")
+  docs.description = docs.description.replace(/[ ]{2,}/g, " ")
+  docs.description = docs.description.replace(/is is/g, "is")
+  const example = docs.description.split("```")
+  if (example.length > 1) {
+    docs.example = example[1]
+  }
+  docs.description = example[0].trim()
+  return docs
+}
+
+/**
+ * This script is very specific to purpose, parsing the handlebars-helpers files to attempt to get information about them.
+ */
+function run() {
+  const foundNames = []
+  for (let collection of COLLECTIONS) {
+    const collectionFile = fs.readFileSync(`../node_modules/handlebars-helpers/lib/${collection}.js`, "utf8")
+    const collectionInfo = {}
+    // collect information about helper
+    let hbsHelperInfo = helpers[collection]()
+    for (let entry of Object.entries(hbsHelperInfo)) {
+      const name = entry[0]
+      // skip built in functions and ones seen already
+      if (
+        HelperFunctionBuiltin.indexOf(name) !== -1 ||
+        foundNames.indexOf(name) !== -1
+      ) {
+        continue
+      }
+      foundNames.push(name)
+      // this is ridiculous, but it parse the function header
+      const fnc = entry[1].toString()
+      const jsDocInfo = getCommentInfo(collectionFile, fnc)
+      let args = jsDocInfo.tags
+        .filter(tag => tag.title === "param")
+        .map(tag => tag.description && tag.description.replace(/`/g, "").split(" ")[0].trim())
+      collectionInfo[name] = fixSpecialCases(name, {
+        args,
+        numArgs: args.length,
+        example: jsDocInfo.example || undefined,
+        description: jsDocInfo.description,
+      })
+    }
+    outputJSON[collection] = collectionInfo
+  }
+  // add the date helper
+  outputJSON["date"] = {
+    "date": {
+      args: [
+        "datetime",
+        "format"
+      ],
+      numArgs: 2,
+      example: "{{date now \"YYYY\"}}",
+      description: "Format a date using moment.js data formatting."
+    }
+  }
+  fs.writeFileSync(FILENAME, JSON.stringify(outputJSON, null, 2))
+}
+
+run()

packages/string-templates/test/helpers.spec.js

@@ -35,6 +35,14 @@ describe("test the math helpers", () => {
     })
     expect(parseInt(output)).toBe(2)
   })
+
+  it("should be able to times", async () => {
+    const output = await processString("{{times a b}}", {
+      a: 5,
+      b: 5,
+    })
+    expect(parseInt(output)).toBe(25)
+  })
 })
 
 describe("test the array helpers", () => {

packages/string-templates/yarn.lock

@@ -1665,6 +1665,13 @@ diffie-hellman@^5.0.0:
     miller-rabin "^4.0.0"
     randombytes "^2.0.0"
 
+doctrine@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/doctrine/-/doctrine-3.0.0.tgz#addebead72a6574db783639dc87a121773973961"
+  integrity sha512-yS+Q5i3hBf7GBkd4KG8a7eBNNWNGLTaEwwYWUijIYM7zrlYDM0BFXHjjPWlWZ1Rg7UaddZeIDmi9jF3HmqiQ2w==
+  dependencies:
+    esutils "^2.0.2"
+
 domexception@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/domexception/-/domexception-2.0.1.tgz#fb44aefba793e1574b0af6aed2801d057529f304"