Fix corner case with 'prettier-ignore' comment whitespace (#98)

* Fix corner case with 'prettier-ignore' comment whitespace

* 0.5.2

* Bump mo-fmt

package.json

@@ -1,6 +1,6 @@
 {
     "name": "prettier-plugin-motoko",
-    "version": "0.5.1",
+    "version": "0.5.2",
     "description": "A code formatter for the Motoko smart contract language.",
     "main": "lib/environments/node.js",
     "browser": "lib/environments/web.js",

packages/mo-fmt/package.json

@@ -1,6 +1,6 @@
 {
     "name": "mo-fmt",
-    "version": "0.5.1",
+    "version": "0.5.2",
     "description": "An easy-to-use Motoko formatter command.",
     "main": "src/cli.js",
     "bin": {
@@ -21,7 +21,7 @@
         "commander": "^9.4.0",
         "fast-glob": "^3.2.11",
         "prettier": "^2.7",
-        "prettier-plugin-motoko": "^0.5.1"
+        "prettier-plugin-motoko": "^0.5.2"
     },
     "devDependencies": {
         "@rollup/plugin-commonjs": "^22.0.2",

src/printers/motoko-tt-ast/print.ts

@@ -298,10 +298,8 @@ function printTokenTree(
                 // allow trailing comma/semicolon if something exists in the group other than a comment
                 allowTrailingSeparator = true;
             }
-            // check for prettier-ignore comments
-            else if (comment === 'prettier-ignore') {
-                ignoringNextStatement = true;
-            }
+
+            const isIgnoreComment = comment === 'prettier-ignore';
 
             if (isSeparator) {
                 endGroup();
@@ -333,7 +331,7 @@ function printTokenTree(
                             : printTokenTree(a, path, options, print, args),
                     );
                 }
-                if (i < trees.length - 1) {
+                if (i < trees.length - 1 && !isIgnoreComment) {
                     resultArray.push(
                         printBetween(trees, i, i + 1, leftMap, rightMap),
                     );
@@ -371,6 +369,10 @@ function printTokenTree(
                         );
                     }
                 }
+
+                if (isIgnoreComment) {
+                    ignoringNextStatement = true;
+                }
             }
         }
         endGroup();

tests/formatter.test.ts

@@ -303,6 +303,10 @@ describe('Motoko formatter', () => {
         expect(format('a<(b,\n//c\n)>()')).toStrictEqual('a<(b, /* c */)>()\n');
     });
 
+    test('prettier-ignore line comment as first line in block', () => {
+        expect(format('{\n// prettier-ignore\n  123}')).toStrictEqual('{\n  // prettier-ignore\n  123\n};\n');
+    });
+
     test('unclosed quotes in comments', () => {
         expect(format("// a'b\n '")).toStrictEqual("// a'b\n';\n");
         expect(format('// a"b\n "')).toStrictEqual('// a"b\n";\n');