feat: add checkMissingCells option to table-column-count (#434)

* feat: add checkMissingCells option to table-column-count * change "will" to "might" in missingCells message * refactor types * rename message id and tweak docs * update examples

Author: TKDev7

docs/rules/table-column-count.md

@@ -58,6 +58,24 @@ Examples of **correct** code for this rule:
 | Single Cell |
 ```
 
+## Options
+
+The following options are available on this rule:
+
+* `checkMissingCells: boolean` - When set to `true`, the rule will also flag rows that have fewer cells than the header row. (default: `false`)
+
+Examples of **incorrect** code when configured as `"table-column-count": ["error", { checkMissingCells: true }]`:
+
+```markdown
+<!-- eslint markdown/table-column-count: ["error", { checkMissingCells: true }] -->
+
+<!-- Data row with fewer cells than header -->
+| Col A | Col B | Col C |
+| ----- | ----- | ----- |
+| 1 | | 3 |
+| 4 | 5 |
+```
+
 ## When Not To Use It
 
 If you intentionally create Markdown tables where data rows are expected to contain more cells than the header, and you have a specific (perhaps non-standard) processing or rendering pipeline that handles this scenario correctly, you might choose to disable this rule. However, adhering to this rule is recommended for typical GFM rendering and data consistency.

src/rules/table-column-count.js

@@ -9,8 +9,8 @@
 
 /**
  * @import { MarkdownRuleDefinition } from "../types.js";
- * @typedef {"inconsistentColumnCount"} TableColumnCountMessageIds
- * @typedef {[]} TableColumnCountOptions
+ * @typedef {"extraCells" | "missingCells"} TableColumnCountMessageIds
+ * @typedef {[{ checkMissingCells?: boolean }]} TableColumnCountOptions
  * @typedef {MarkdownRuleDefinition<{ RuleOptions: TableColumnCountOptions, MessageIds: TableColumnCountMessageIds }>} TableColumnCountRuleDefinition
  */
 
@@ -31,12 +31,30 @@ export default {
 },
 
 messages: {
-inconsistentColumnCount:
+extraCells:
 "Table column count mismatch (Expected: {{expectedCells}}, Actual: {{actualCells}}), extra data starting here will be ignored.",
+missingCells:
+"Table column count mismatch (Expected: {{expectedCells}}, Actual: {{actualCells}}), row might be missing data.",
 },
+
+schema: [
+{
+type: "object",
+properties: {
+checkMissingCells: {
+type: "boolean",
+},
+},
+additionalProperties: false,
+},
+],
+
+defaultOptions: [{ checkMissingCells: false }],
 },
 
 create(context) {
+const [{ checkMissingCells }] = context.options;
+
 return {
 table(node) {
 if (node.children.length < 1) {
@@ -49,20 +67,39 @@ export default {
 for (let i = 1; i < node.children.length; i++) {
 const currentRow = node.children[i];
 const actualCellsLength = currentRow.children.length;
+const lastActualCellNode =
+currentRow.children[actualCellsLength - 1];
 
 if (actualCellsLength > expectedCellsLength) {
 const firstExtraCellNode =
 currentRow.children[expectedCellsLength];
 
-const lastActualCellNode =
-currentRow.children[actualCellsLength - 1];
-
 context.report({
 loc: {
 start: firstExtraCellNode.position.start,
 end: lastActualCellNode.position.end,
 },
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
+data: {
+actualCells: String(actualCellsLength),
+expectedCells: String(expectedCellsLength),
+},
+});
+} else if (
+checkMissingCells &&
+actualCellsLength < expectedCellsLength
+) {
+context.report({
+loc: {
+start: {
+column:
+lastActualCellNode.position.end.column -
+1,
+line: lastActualCellNode.position.end.line,
+},
+end: currentRow.position.end,
+},
+messageId: "missingCells",
 data: {
 actualCells: String(actualCellsLength),
 expectedCells: String(expectedCellsLength),

tests/rules/table-column-count.test.js

@@ -88,6 +88,24 @@ ruleTester.run("table-column-count", rule, {
 | abc | def |
 | --- | --- |
 `,
+{
+code: dedent`
+ | Header | Header |
+ | ------ | ------ |
+ | Cell | Cell |
+ | Cell | Cell |
+	`,
+options: [{ checkMissingCells: true }],
+},
+{
+code: dedent`
+ | Header | Header |
+ | ------ | ------ |
+ | Cell | |
+ | Cell | Cell |
+	`,
+options: [{ checkMissingCells: true }],
+},
 ],
 
 invalid: [
@@ -99,7 +117,7 @@ ruleTester.run("table-column-count", rule, {
  `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 3,
 column: 17,
@@ -116,7 +134,7 @@ ruleTester.run("table-column-count", rule, {
  `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "4", expectedCells: "2" },
 line: 3,
 column: 17,
@@ -133,7 +151,7 @@ ruleTester.run("table-column-count", rule, {
  `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "2", expectedCells: "1" },
 line: 3,
 column: 5,
@@ -155,7 +173,7 @@ ruleTester.run("table-column-count", rule, {
  `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 5,
 column: 21,
@@ -173,7 +191,7 @@ ruleTester.run("table-column-count", rule, {
  `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 4,
 column: 11,
@@ -191,7 +209,7 @@ ruleTester.run("table-column-count", rule, {
 `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 3,
 column: 13,
@@ -209,15 +227,15 @@ ruleTester.run("table-column-count", rule, {
 `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 3,
 column: 13,
 endLine: 3,
 endColumn: 23,
 },
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 4,
 column: 13,
@@ -236,15 +254,15 @@ ruleTester.run("table-column-count", rule, {
 `,
 errors: [
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 3,
 column: 13,
 endLine: 3,
 endColumn: 23,
 },
 {
-messageId: "inconsistentColumnCount",
+messageId: "extraCells",
 data: { actualCells: "3", expectedCells: "2" },
 line: 5,
 column: 13,
@@ -253,5 +271,154 @@ ruleTester.run("table-column-count", rule, {
 },
 ],
 },
+{
+code: dedent`
+ | Header | Header | Header |
+ | ------ | ------ | ------ |
+ | Cell | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "missingCells",
+data: { actualCells: "2", expectedCells: "3" },
+line: 3,
+column: 19,
+endLine: 3,
+endColumn: 20,
+},
+],
+},
+{
+code: dedent`
+ | Col A | Col B | Col C |
+ | ----- | ----- | ----- |
+ | Cell | | Cell |
+ | Cell | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "missingCells",
+data: { actualCells: "2", expectedCells: "3" },
+line: 4,
+column: 17,
+endLine: 4,
+endColumn: 18,
+},
+],
+},
+{
+code: dedent`
+ | Col A | Col B | Col C |
+ | ----- | ----- | ----- |
+ | Cell |
+ | Cell | Cell |
+ | Cell | Cell | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "missingCells",
+data: { actualCells: "1", expectedCells: "3" },
+line: 3,
+column: 9,
+endLine: 3,
+endColumn: 10,
+},
+{
+messageId: "missingCells",
+data: { actualCells: "2", expectedCells: "3" },
+line: 4,
+column: 17,
+endLine: 4,
+endColumn: 18,
+},
+],
+},
+{
+code: dedent`
+ | Table |
+ | ----- |
+ | Cell | Cell |
+ | Cell |
+ | Cell | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "extraCells",
+data: { actualCells: "2", expectedCells: "1" },
+line: 3,
+column: 9,
+endLine: 3,
+endColumn: 18,
+},
+{
+messageId: "extraCells",
+data: { actualCells: "2", expectedCells: "1" },
+line: 5,
+column: 9,
+endLine: 5,
+endColumn: 18,
+},
+],
+},
+{
+code: dedent`
+ | Table | Header |
+ | ----- | ------ |
+ | Cell | Cell | Cell |
+ | Cell |
+ | Cell | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "extraCells",
+data: { actualCells: "3", expectedCells: "2" },
+line: 3,
+column: 18,
+endLine: 3,
+endColumn: 28,
+},
+{
+messageId: "missingCells",
+data: { actualCells: "1", expectedCells: "2" },
+line: 4,
+column: 9,
+endLine: 4,
+endColumn: 10,
+},
+],
+},
+{
+code: dedent`
+ | Table | Header | Header |
+ | ----- | ------ | ------ |
+ | Cell | Cell | Cell |
+ | Cell | Cell | Cell | Cell |
+ | Cell |
+ `,
+options: [{ checkMissingCells: true }],
+errors: [
+{
+messageId: "extraCells",
+data: { actualCells: "4", expectedCells: "3" },
+line: 4,
+column: 27,
+endLine: 4,
+endColumn: 37,
+},
+{
+messageId: "missingCells",
+data: { actualCells: "1", expectedCells: "3" },
+line: 5,
+column: 9,
+endLine: 5,
+endColumn: 10,
+},
+],
+},
 ],
 });