feature: @nirguna/printer-wasm: lint-formatting: add missing-indent rule

Author: coderaiser

packages/printer-wasm/test/lint-formatting/lint.js

@@ -1,17 +1,28 @@
 import * as indent from './rules/indent.js';
 import * as blankLine from './rules/blank-line.js';
 import * as trailingSpace from './rules/trailing-space.js';
+import * as missingIndent from './rules/missing-indent.js';
 
-const rules = [indent, trailingSpace, blankLine];
+const rules = [
+    indent,
+    trailingSpace,
+    blankLine,
+    missingIndent,
+];
 
 export const lint = (text) => {
     const issues = [];
     const lines = text.split('\n');
 
     for (const [i, line] of lines.entries()) {
+        const next = lines[i + 1];
+        const context = {
+            isFirstLine: !i,
+            isLastLine: i === lines.length - 1,
+        };
+        
         for (const rule of rules) {
-            const next = lines[i + 1];
-            const position = rule.check(line, next);
+            const position = rule.check(line, next, context);
 
             if (position)
                 issues.push({

packages/printer-wasm/test/lint-formatting/rules/missing-indent.js

@@ -0,0 +1,16 @@
+export const report = () => 'missing indent';
+
+export const check = (line, _, {isFirstLine, isLastLine}) => {
+    if (isFirstLine || isLastLine)
+        return null;
+    
+    if (line.trim() === '')
+        return null;
+    
+    if (line.startsWith('s'))
+        return null;
+    
+    return {
+        index: 0,
+    };
+};

packages/printer-wasm/test/lint-formatting/rules/missing-indent.spec.js

@@ -0,0 +1,131 @@
+import {test} from 'supertape';
+import {montag} from 'montag';
+import {check} from './missing-indent.js';
+
+test('missing-indent: flags an unindented line', (t) => {
+    const position = check('(memory 1)', undefined, {
+        isFirstLine: false,
+        isLastLine: false,
+    });
+    
+    t.deepEqual(position, {
+        index: 0,
+    });
+    t.end();
+});
+
+test('missing-indent: first line is exempt', (t) => {
+    const position = check('(module', undefined, {
+        isFirstLine: true,
+        isLastLine: false,
+    });
+    
+    t.notOk(position);
+    t.end();
+});
+
+test('missing-indent: last line is exempt', (t) => {
+    const position = check(')', undefined, {
+        isFirstLine: false,
+        isLastLine: true,
+    });
+    
+    t.notOk(position);
+    t.end();
+});
+
+test('missing-indent: blank line is not flagged', (t) => {
+    const position = check('', undefined, {
+        isFirstLine: false,
+        isLastLine: false,
+    });
+    
+    t.notOk(position);
+    t.end();
+});
+
+test('missing-indent: correctly indented line passes', (t) => {
+    const position = check('    (memory 1)', undefined, {
+        isFirstLine: false,
+        isLastLine: false,
+    });
+    
+    t.notOk(position);
+    t.end();
+});
+
+test('missing-indent: catches the broken-after-table shape from step 0', (t) => {
+    const source = montag`
+        (module
+            (table 1 2 anyfunc)
+        (memory 1)
+        (export "x" (func $x))
+        (func $x)
+        )
+    `;
+    
+    const lines = source.split('\n');
+    
+    const ctx = (i) => ({
+        isFirstLine: !i,
+        isLastLine: i === lines.length - 1,
+    });
+    
+    const flagLines = [2, 3, 4];
+    
+    for (const i of flagLines) {
+        const position = check(lines[i], lines[i + 1], ctx(i));
+        t.equal(position?.index, 0, `line ${i + 1} should be flagged`);
+    }
+    
+    t.end();
+});
+
+test('missing-indent: closing paren at the end is exempt', (t) => {
+    const source = montag`
+        (module
+        (memory 1)
+        )
+    `;
+    
+    const lines = source.split('\n');
+    
+    const ctx = (i) => ({
+        isFirstLine: !i,
+        isLastLine: i === lines.length - 1,
+    });
+    
+    for (const [i, line] of lines.entries()) {
+        const position = check(line, lines[i + 1], ctx(i));
+        t.notOk(position, `line ${i + 1} should be exempt`);
+    }
+    
+    t.end();
+});
+
+test('missing-indent: catches the broken-after-elem shape from step 0', (t) => {
+    const source = montag`
+        (module
+            (elem (i32.const 0) $x $y)
+        (table 1 2 anyfunc)
+            (func $x)
+            (func $y)
+        )
+    `;
+    
+    const lines = source.split('\n');
+    
+    const ctx = (i) => ({
+        isFirstLine: !i,
+        isLastLine: i === lines.length - 1,
+    });
+    
+    const flagLines = [2];
+    
+    for (const i of flagLines) {
+        const position = check(lines[i], lines[i + 1], ctx(i));
+        t.equal(position?.index, 0, `line ${i + 1} should be flagged`);
+    }
+    
+    t.end();
+});