From 005959df3923395774efd14582e17e60abc67d64 Mon Sep 17 00:00:00 2001
From: coderaiser <coderaiser@cloudcmd.io>
Date: Thu, 19 Oct 2023 23:06:59 +0300
Subject: [PATCH] feature: goldstein: convert: if let

---
 packages/convert/apply-if-let/index.js    | 18 ++++++++++++++++++
 packages/convert/index.js                 |  2 ++
 packages/convert/index.spec.js            | 23 +++++++++++++++++++++++
 packages/printer/visitors/if-statement.js |  3 ++-
 4 files changed, 45 insertions(+), 1 deletion(-)
 create mode 100644 packages/convert/apply-if-let/index.js

diff --git a/packages/convert/apply-if-let/index.js b/packages/convert/apply-if-let/index.js
new file mode 100644
index 0000000..5aeadea
--- /dev/null
+++ b/packages/convert/apply-if-let/index.js
@@ -0,0 +1,18 @@
+import {types} from 'putout';
+const {
+    VariableDeclaration,
+    VariableDeclarator,
+} = types;
+
+export const report = () => `Use 'add-array'`;
+export const replace = () => ({
+    '{let __a = __b; if (__c) __d}': ({__a, __b}, path) => {
+        const ifPath = path.get('body.1');
+        ifPath.node.test = VariableDeclaration('let', [
+            VariableDeclarator(__a, __b),
+        ]);
+        
+        return ifPath;
+    },
+});
+
diff --git a/packages/convert/index.js b/packages/convert/index.js
index 66f7ccc..4bab979 100644
--- a/packages/convert/index.js
+++ b/packages/convert/index.js
@@ -4,6 +4,7 @@ import {print} from '../printer/index.js';
 import * as removeImportTry from './remove-import-try/index.js';
 import * as applyTry from './apply-try/index.js';
 import * as addArray from './add-array/index.js';
+import * as applyIfLet from './apply-if-let/index.js';
 import {
     fixEmpty,
     parse,
@@ -15,6 +16,7 @@ export const convert = (source) => {
     transform(ast, source, {
         plugins: [
             ['add-array', addArray],
+            ['apply-if-let', applyIfLet],
             ['apply-try', applyTry],
             ['remove-import-try', removeImportTry],
         ],
diff --git a/packages/convert/index.spec.js b/packages/convert/index.spec.js
index be8dddb..9cfae0e 100644
--- a/packages/convert/index.spec.js
+++ b/packages/convert/index.spec.js
@@ -44,3 +44,26 @@ test('goldstein: convert: add-array', (t) => {
     t.equal(result, expected);
     t.end();
 });
+
+test('goldstein: convert: convert-if-let', (t) => {
+    const source = montag`
+        {
+            let a = b?.c;
+            
+            if (a) {
+                log(a);
+            }
+        }
+    `;
+    
+    const result = convert(source);
+    
+    const expected = montag`
+        if let a = b?.c {
+            log(a);
+        }\n
+    `;
+    
+    t.equal(result, expected);
+    t.end();
+});
diff --git a/packages/printer/visitors/if-statement.js b/packages/printer/visitors/if-statement.js
index 8f273e8..5da34a1 100644
--- a/packages/printer/visitors/if-statement.js
+++ b/packages/printer/visitors/if-statement.js
@@ -1,12 +1,13 @@
 import {visitors as v} from '@putout/printer';
 
 export const IfStatement = (path, printer, semantics) => {
-    const {print} = printer;
+    const {print, indent} = printer;
     const {node} = path;
     
     if (!node.goldsteinIf)
         return v.IfStatement(path, printer, semantics);
     
+    indent();
     print('if ');
     print('__test');
     print(' ');