feat: allow context access in liquidMethodMissing, #808 (#820)

src/context/context.ts

@@ -86,7 +86,7 @@ export class Context {
   public * _getFromScope (scope: unknown, paths: (PropertyKey | Drop)[] | string, strictVariables = this.strictVariables): IterableIterator<unknown> {
     if (isString(paths)) paths = paths.split('.')
     for (let i = 0; i < paths.length; i++) {
-      scope = yield readProperty(scope as object, paths[i], this.ownPropertyOnly)
+      scope = yield this.readProperty(scope as object, paths[i])
       if (strictVariables && isUndefined(scope)) {
         throw new InternalUndefinedVariableError((paths as string[]).slice(0, i + 1).join!('.'))
       }
@@ -120,21 +120,21 @@ export class Context {
     if (key in this.environments) return this.environments
     return this.globals
   }
+  readProperty (obj: Scope, key: (PropertyKey | Drop)) {
+    obj = toLiquid(obj)
+    key = toValue(key) as PropertyKey
+    if (isNil(obj)) return obj
+    if (isArray(obj) && (key as number) < 0) return obj[obj.length + +key]
+    const value = readJSProperty(obj, key, this.ownPropertyOnly)
+    if (value === undefined && obj instanceof Drop) return obj.liquidMethodMissing(key, this)
+    if (isFunction(value)) return value.call(obj)
+    if (key === 'size') return readSize(obj)
+    else if (key === 'first') return readFirst(obj)
+    else if (key === 'last') return readLast(obj)
+    return value
+  }
 }
 
-export function readProperty (obj: Scope, key: (PropertyKey | Drop), ownPropertyOnly: boolean) {
-  obj = toLiquid(obj)
-  key = toValue(key) as PropertyKey
-  if (isNil(obj)) return obj
-  if (isArray(obj) && (key as number) < 0) return obj[obj.length + +key]
-  const value = readJSProperty(obj, key, ownPropertyOnly)
-  if (value === undefined && obj instanceof Drop) return obj.liquidMethodMissing(key)
-  if (isFunction(value)) return value.call(obj)
-  if (key === 'size') return readSize(obj)
-  else if (key === 'first') return readFirst(obj)
-  else if (key === 'last') return readLast(obj)
-  return value
-}
 export function readJSProperty (obj: Scope, key: PropertyKey, ownPropertyOnly: boolean) {
   if (ownPropertyOnly && !hasOwnProperty.call(obj, key) && !(obj instanceof Drop)) return undefined
   return obj[key]

src/drop/drop.ts

@@ -1,5 +1,7 @@
+import { Context } from '../context'
+
 export abstract class Drop {
-  public liquidMethodMissing (key: string | number): Promise<any> | any {
+  public liquidMethodMissing (key: string | number, context: Context): Promise<any> | any {
     return undefined
   }
 }

test/e2e/drop.spec.ts

@@ -1,25 +1,37 @@
-import { Drop, Liquid } from '../..'
-
-class SettingsDrop extends Drop {
-  public foo = 'FOO'
-  public bar () {
-    return 'BAR'
-  }
-  public liquidMethodMissing (key: string) {
-    return key.toUpperCase()
-  }
-}
+import { Context, Drop, Liquid } from '../..'
 
 describe('drop', function () {
-  const settings = new SettingsDrop()
   let engine: Liquid
   beforeEach(function () {
     engine = new Liquid()
   })
-  it('should support liquidMethodMissing', async function () {
-    const src = `{{settings.foo}},{{settings.bar}},{{settings.coo}}`
-    const html = await engine.parseAndRender(src, { settings })
-    return expect(html).toBe('FOO,BAR,COO')
+
+  describe('liquidMethodMissing', () => {
+    it('should support liquidMethodMissing', async function () {
+      class SettingsDrop extends Drop {
+        public foo = 'FOO'
+        public bar () {
+          return 'BAR'
+        }
+        public liquidMethodMissing (key: string) {
+          return key.toUpperCase()
+        }
+      }
+      const src = `{{settings.foo}},{{settings.bar}},{{settings.coo}}`
+      const html = await engine.parseAndRender(src, { settings: new SettingsDrop() })
+      return expect(html).toBe('FOO,BAR,COO')
+    })
+
+    it('should expose context', async function () {
+      class SettingsDrop extends Drop {
+        public liquidMethodMissing (key: string, context: Context) {
+          return key + ':' + context.getSync([key])
+        }
+      }
+      const src = `{{settings.foo}}`
+      const html = await engine.parseAndRender(src, { settings: new SettingsDrop(), foo: 'FOO' })
+      return expect(html).toBe('foo:FOO')
+    })
   })
 
   describe('BlandDrop', function () {