modifier context and materialize flags

Author: mattfysh

package.json

@@ -18,9 +18,9 @@
     "test"
   ],
   "devDependencies": {
-    "@biomejs/biome": "^2.2.3",
+    "@biomejs/biome": "^2.2.4",
     "@changesets/changelog-github": "^0.5.1",
-    "@changesets/cli": "^2.29.6",
+    "@changesets/cli": "^2.29.7",
     "@types/bun": "^1.2.21",
     "knip": "^5.63.1",
     "sherif": "^1.6.1",

packages/get/src/calls.ts

@@ -16,7 +16,9 @@ export async function callModifier(
 ) {
   const entry = await registry.importMod(mod)
   if (entry) {
-    return entry.mod(context?.data, args)
+    const ctx =
+      context && entry.materialize ? materialize(context) : context?.data
+    return entry.mod(ctx, args)
   }
 
   invariant(context, 'Modifier requires context')

packages/get/src/execute.ts

@@ -107,7 +107,7 @@ export async function execute(
       async SliceExpr({ slice, typeInfo }) {
         try {
           const ctx = scope.context
-          const deps = ctx && materialize(ctx)
+          const deps = ctx ? materialize(ctx) : {}
           const ret = await hooks.slice(slice.value, deps)
           const data =
             ret === undefined ? new lib.NullSelection('<slice>') : ret
@@ -158,12 +158,9 @@ export async function execute(
       },
 
       async ModifierExpr(node) {
-        const data = await callModifier(
-          registry,
-          node.modifier.value,
-          node.args.data,
-          scope.context,
-        )
+        const mod = node.modifier.value
+        const args = materialize(node.args)
+        const data = await callModifier(registry, mod, args, scope.context)
         return { data, typeInfo: node.typeInfo }
       },
 

packages/get/src/registry.ts

@@ -3,13 +3,11 @@ import { Type } from '@getlang/ast'
 import type { Hooks, Modifier } from '@getlang/lib'
 import { RecursiveCallError, ValueTypeError } from '@getlang/lib/errors'
 import { analyze, desugar, inference, parse } from '@getlang/parser'
-import type { Pattern } from 'acorn'
-import { parse as acorn } from 'acorn'
-import { traverse } from 'estree-toolkit'
 
 type ModEntry = {
   mod: Modifier
   useContext: boolean
+  materialize: boolean
   returnType: TypeInfo
 }
 
@@ -53,31 +51,6 @@ function buildImportKey(module: string, typeInfo?: TypeInfo) {
   return key
 }
 
-function inferContext(mod: Modifier) {
-  const src = mod.toString()
-  const ast = acorn(src, { ecmaVersion: 'latest' })
-  let useContext = false
-  traverse(ast, {
-    $: { scope: true },
-    Program(path) {
-      const fn = ast.body[0]
-      let ctxParam: Pattern | undefined
-      if (fn?.type === 'FunctionDeclaration') {
-        ctxParam = fn.params[0]
-      } else if (fn?.type === 'ExpressionStatement') {
-        if (fn.expression.type === 'ArrowFunctionExpression') {
-          ctxParam = fn.expression.params[0]
-        }
-      }
-      const fnScope = path.scope?.children[0]
-      const bindings = Object.values(fnScope?.bindings || {})
-      const ctxBinding = bindings.find(b => b?.identifierPath.node === ctxParam)
-      useContext = Boolean(ctxBinding?.references.length)
-    },
-  })
-  return useContext
-}
-
 export class Registry {
   private info: Record<string, Promise<Info>> = {}
   private entries: Record<string, Promise<Entry>> = {}
@@ -91,10 +64,20 @@ export class Registry {
       if (!compiled) {
         return null
       }
-      const fn = compiled.modifier
-      const useContext = inferContext(fn)
-      const returnType = compiled.typeInfo || { type: Type.Value }
-      return { mod: fn, useContext, returnType }
+
+      const {
+        modifier: fn,
+        useContext = false,
+        materialize = true,
+        returnType = { type: Type.Value },
+      } = compiled
+
+      return {
+        mod: fn,
+        useContext,
+        materialize,
+        returnType,
+      }
     })
     return this.modifiers[mod]
   }

packages/lib/src/core/hooks.ts

@@ -28,7 +28,9 @@ export type Modifier = (context: any, options: Record<string, unknown>) => any
 export type ModifierHook = (modifier: string) => MaybePromise<
   | {
       modifier: Modifier
-      typeInfo?: TypeInfo
+      useContext?: boolean
+      materialize?: boolean
+      returnType?: TypeInfo
     }
   | undefined
 >

packages/parser/package.json

@@ -30,7 +30,7 @@
     "@types/nearley": "^2.11.5",
     "acorn": "^8.15.0",
     "estree-toolkit": "^1.7.13",
-    "globals": "^16.3.0",
+    "globals": "^16.4.0",
     "lodash-es": "^4.17.21",
     "moo": "^0.5.2",
     "nearley": "^2.20.1",

packages/parser/src/passes/desugar.ts

@@ -23,7 +23,7 @@ const visitors = [
   dropDrills,
 ]
 
-export function desugar(ast: Program, macros: string[] = []) {
+export function desugar(ast: Program, macros: string[] = []): Program {
   const parsers = new RequestParsers()
   const program = visitors.reduce((ast, pass) => {
     parsers.reset()

packages/parser/src/passes/inference/calls.ts

@@ -3,7 +3,7 @@ import { isToken } from '@getlang/ast'
 import { transform } from '@getlang/walker'
 import { LineageTracker } from '../lineage.js'
 
-export function registerCalls(ast: Program, macros: string[] = []) {
+export function registerCalls(ast: Program, macros: string[] = []): Program {
   const scope = new LineageTracker()
 
   function registerCall(node: Expr) {

packages/parser/src/passes/inference/typeinfo.ts

@@ -267,7 +267,7 @@ export function resolveTypes(ast: Program, options: ResolveTypeOptions) {
     },
   }
 
-  const program = transform(ast, { scope, ...visitor })
+  const program: Program = transform(ast, { scope, ...visitor })
   const returnType = ex?.typeInfo ?? { type: Type.Never }
 
   return { program, returnType: returnType }

test/helpers.ts

@@ -1,6 +1,6 @@
 import { expect } from 'bun:test'
 import { executeModule } from '@getlang/get'
-import type { Hooks, Inputs, MaybePromise, ModifierHook } from '@getlang/lib'
+import type { Hooks, Inputs, MaybePromise } from '@getlang/lib'
 import { invariant } from '@getlang/lib'
 import { ImportError } from '@getlang/lib/errors'
 import { desugar, parse, print } from '@getlang/parser'
@@ -9,7 +9,6 @@ import './expect.js'
 
 type ExecuteOptions = Partial<{
   fetch: Fetch
-  modifier: ModifierHook
   willThrow: boolean
   hooks: Hooks
 }>
@@ -29,7 +28,7 @@ export async function execute(
   inputs?: Inputs,
   options: ExecuteOptions = {},
 ): Promise<any> {
-  const { fetch, modifier, willThrow } = options
+  const { fetch, willThrow } = options
   const normalized = typeof program === 'string' ? { Home: program } : program
   const modules: Record<string, string> = {}
   for (const [name, source] of Object.entries(normalized)) {
@@ -40,7 +39,6 @@ export async function execute(
   }
 
   const hooks: Hooks = {
-    modifier,
     import(module) {
       const src = modules[module]
       invariant(src, new ImportError(`Failed to import module: ${module}`))