feature: add should keyword (#5)

* Add should keyword

* Fix bad spelling

Co-authored-by: Giorgio Bellisario <{ID}+{username}@users.noreply.github.com>

README.md

@@ -149,6 +149,25 @@ import tryToCatch from 'try-catch';
 const [error, result] = await tryToCatch(1, 2, 3);
 ```
 
+### `should`
+
+`should` can be used as an expression.
+This keyword is useful if you want to prevent a function call (also async) to throw an error because you don't need to have any result and the real execution is just optional (so runs if supported).
+
+```gs
+should hello()
+```
+
+Is the same as:
+
+```js
+try {
+    hello();
+} catch (e) {};
+```
+
+> Warning: this feature can be helpful but also dangerous especially if you're debugging your application. In fact, this is made to be used as an optional function call (ex. should load content, but not necessary and knowing this feature is optional), if you call a function in this way while debugging, no error will be printed and the application will continue run as nothing happened.
+
 ### `if`
 
 You can omit parens. But you must use braces in this case.

packages/keyword-should/fixture/await-should.gs

@@ -0,0 +1 @@
+should await hello()

packages/keyword-should/fixture/await-should.js

@@ -0,0 +1,3 @@
+try {
+    await hello();
+} catch (e) {};

packages/keyword-should/fixture/not-supported.gs

@@ -0,0 +1,4 @@
+should {
+    var a = "hello"
+    console.log(a)
+}

packages/keyword-should/fixture/should.gs

@@ -0,0 +1 @@
+should hello()

packages/keyword-should/fixture/should.js

@@ -0,0 +1,3 @@
+try {
+    hello();
+} catch (e) {};

packages/keyword-should/index.js

@@ -0,0 +1,99 @@
+import {types} from 'putout';
+import {
+    addKeyword,
+    TokenType,
+    tokTypes as tt,
+} from '../operator/index.js';
+
+const {
+    isCallExpression,
+    isAwaitExpression,
+} = types;
+
+export default function newSpeak(Parser) {
+    const {keywordTypes} = Parser.acorn;
+    keywordTypes.should = new TokenType('should', {
+        keyword: 'should',
+    });
+
+    return class extends Parser {
+        parse() {
+            this.keywords = addKeyword('should', this.keywords);
+            return super.parse();
+        }
+        parseStatement(context, topLevel, exports) {
+            if (this.type === keywordTypes.should) {
+                return this.parseShould();
+            }
+
+            return super.parseStatement(context, topLevel, exports);
+        }
+
+        parseShould() {
+            this.next();
+
+            const node = super.startNode();
+
+            if (this.type === tt.braceL)
+                return this.raise(this.start, `After 'should' only 'await' and 'function call' can come, brakets are not suppoted`);
+
+            const expression = this.parseExpression();
+
+            if (isCallExpression(expression))
+                node.expression = {
+                    type: 'TryStatement',
+                    block: {
+                        type: 'BlockStatement',
+                        body: [{
+                            type: 'ExpressionStatement',
+                            expression: {
+                                type: 'CallExpression',
+                                callee: expression.callee,
+                                arguments: expression.arguments.slice(),
+                            },
+                        }],
+                    },
+                    handler: {
+                        type: 'CatchClause',
+                        param: {
+                            type: 'Identifier',
+                            name: 'e',
+                        },
+                        body: {
+                            type: 'BlockStatement',
+                            body: [],
+                        },
+                    },
+                };
+
+            else if (isAwaitExpression(expression))
+                node.expression = {
+                    type: 'TryStatement',
+                    block: {
+                        type: 'BlockStatement',
+                        body: [{
+                            type: 'ExpressionStatement',
+                            expression,
+                        }],
+                    },
+                    handler: {
+                        type: 'CatchClause',
+                        param: {
+                            type: 'Identifier',
+                            name: 'e',
+                        },
+                        body: {
+                            type: 'BlockStatement',
+                            body: [],
+                        },
+                    },
+                };
+
+            else
+                this.raise(this.start, `After 'should' only 'await' and 'function call' can come`);
+
+            return super.finishNode(node, 'ExpressionStatement');
+        }
+    };
+}
+

packages/keyword-should/index.spec.js

@@ -0,0 +1,19 @@
+import {createTest} from '../test/index.js';
+import keywordFn from './index.js';
+
+const test = createTest(import.meta.url, keywordFn);
+
+test('goldstein: keyword: should', (t) => {
+    t.compile('should');
+    t.end();
+});
+
+test('goldstein: keyword: should (with await)', (t) => {
+    t.compile('await-should');
+    t.end();
+});
+
+test('goldstein: keyword: should (brakets)', (t) => {
+    t.raise('not-supported', `After 'should' only 'await' and 'function call' can come, brakets are not suppoted (1:7)`);
+    t.end();
+});