Start the development of a plugin for Prettier

tools/prettier-plugin-cadence/.gitignore

@@ -0,0 +1 @@
+dist

tools/prettier-plugin-cadence/README.md

@@ -0,0 +1,19 @@
+# Cadence Plugin for Prettier
+
+Current status: 🚧 Under construction, not ready for use yet
+
+## Development
+
+### Getting Started
+
+* Compile the Cadence parser tool: `go build ../../runtime/cmd/parse`
+* Install the dependencies: `npm install`
+* Compile the plugin: `npx tsc`
+* Try the plugin on a test file: `npx prettier test.cdc --plugin=.`
+
+### Notes
+
+- The Prettier Playground is very useful for determining what documents to generate,
+  e.g. https://prettier.io/playground/#N4Igxg9gdgLgprEAuEAdKAzArlMMCW0ABAIYAUYSRUWAtgEZwBOANEQCZUDOMT+UAcwCUVfjCLB0RIvXQBfdCBYgIABwLQuyUCSZMIAdwAKuhFpQkANgZIBPLcvpMSYANZwYAZVUv+A5LxYcMoAFjC0lgDqIfjwXD5gcJ5msfgAbrG2yOBcDiD8XMwwRs4CtCTIGFaFygBWXAAeAELObh6eJLRwADL8cJXVwSD1DZ5+lnAAilgQ8AOWNSA+TIVM2TC2qnBcYHzqSkt8sJH47DAhyAAcAAzKqvqFkc6q2ffbzGn9ygCOM-AlanMIBIXAAtFA4HB2FCDkw4L98HCSiQyhUkFUFkNCrR8PNFlxxlM-v10YNlDASPQTmcLkgACzk5z4Sx+ADCEFo5Wy2wArAcsIUACqU8wYxZpIIASSg0Ngnl2+HUAEEZZ4NhM8XA5HIgA
+
+

tools/prettier-plugin-cadence/package.json

@@ -0,0 +1,21 @@
+{
+  "name": "prettier-plugin-cadence",
+  "version": "0.1.0",
+  "description": "",
+  "main": "dist",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "author": "",
+  "license": "Apache-2.0",
+  "devDependencies": {
+    "@types/execa": "^2.0.0",
+    "@types/node": "^14.0.27",
+    "@types/prettier": "^2.0.2",
+    "prettier": "^2.0.5",
+    "typescript": "^3.9.7"
+  },
+  "dependencies": {
+    "execa": "^4.0.3"
+  }
+}

tools/prettier-plugin-cadence/src/index.ts

@@ -0,0 +1,32 @@
+import {parse} from "./parse";
+import {print} from "./print";
+
+export const languages = [
+  {
+    name: "Cadence",
+    parsers: ["cadence"],
+    since: "1.0.0",
+    extensions: [".cdc"],
+    tmScope: "source.cadence",
+    vscodeLanguageIds: ["cadence"],
+  },
+];
+
+export const parsers = {
+  cadence: {
+    parse,
+    astFormat: "cadence",
+    locStart(node: any) {
+      return node.StartPos.Offset;
+    },
+    locEnd(node: any) {
+      return node.EndPos.Offset;
+    },
+  },
+};
+
+export const printers = {
+  "cadence": {
+    print,
+  },
+};

tools/prettier-plugin-cadence/src/nodes.ts

@@ -0,0 +1,39 @@
+
+export type Node =
+  | Program
+  | Declaration
+  | Expression
+
+export interface Identifier {
+  Identifier: string
+}
+
+export interface Program {
+  Type: "Program"
+  Declarations: Declaration[]
+}
+
+// Declarations
+
+export type Declaration =
+  FunctionDeclaration
+
+export interface FunctionDeclaration {
+  Type: "FunctionDeclaration"
+  Identifier: Identifier
+}
+
+// Expressions
+
+export type Expression =
+  StringExpression
+  | NilExpression
+
+export interface NilExpression {
+  Type: "NilExpression"
+}
+
+interface StringExpression {
+  Type: "StringExpression"
+  Value: string
+}

tools/prettier-plugin-cadence/src/parse.ts

@@ -0,0 +1,15 @@
+import {AST, Parser, ParserOptions} from "prettier";
+import * as execa from "execa"
+
+export function parse(
+  text: string,
+  parsers: { [parserName: string]: Parser },
+  opts: ParserOptions,
+): AST | null {
+  const returnValue = execa.sync("./parse", ['--json'], {input: text});
+  const result = JSON.parse(returnValue.stdout)[0]
+  if (result.Error) {
+    return null
+  }
+  return result.Program
+}

tools/prettier-plugin-cadence/src/print.ts

@@ -0,0 +1,45 @@
+import {doc, Doc, FastPath} from "prettier";
+import {Node} from "./nodes";
+import concat = doc.builders.concat;
+import hardline = doc.builders.hardline;
+import join = doc.builders.join;
+import group = doc.builders.group;
+
+export function print(
+  path: FastPath<Node>,
+  options: object,
+  print: (path: FastPath) => Doc
+): Doc | null {
+  const n = path.getValue();
+  switch (n.Type) {
+    case "StringExpression":
+      return concat(['"', n.Value, '"'])
+
+    case "NilExpression":
+      return "nil"
+
+    case "Program":
+      const parts = path.map(print, 'Declarations')
+
+      // Only force a trailing newline if there were any contents.
+      if (n.Declarations.length) {
+        parts.push(hardline);
+      }
+
+      return join(hardline, parts)
+
+    case "FunctionDeclaration":
+      return concat([
+        "fun ",
+        n.Identifier.Identifier,
+        group(concat(['(', ')'])),
+        " ",
+        "{",
+        "}"
+      ])
+
+    default:
+      const some: {Type: string} = n
+      throw new Error(`unsupported AST node: ${some.Type}`)
+  }
+}

tools/prettier-plugin-cadence/test.cdc

@@ -0,0 +1 @@
+  pub  fun hello() { }

tools/prettier-plugin-cadence/tsconfig.json

@@ -0,0 +1,14 @@
+
+{
+  "compilerOptions": {
+    "esModuleInterop": true,
+    "inlineSourceMap": true,
+    "lib": ["es2016"],
+    "moduleResolution": "node",
+    "outDir": "dist",
+    "rootDir": "src",
+    "strict": true
+  },
+  "include": ["src/**/*"]
+}
+