feat(lint): add rules for lowercase file names, max line length and no tab indentation

src/rules/lowerCaseFileNames.spec.ts

@@ -0,0 +1,27 @@
+import { Severity } from '../types/Severity'
+import { lowerCaseFileNames } from './lowerCaseFileNames'
+
+describe('lowerCaseFileNames', () => {
+  it('should return an empty array when the file name has no uppercase characters', () => {
+    const filePath = '/code/sas/my_sas_file.sas'
+    expect(lowerCaseFileNames.test(filePath)).toEqual([])
+  })
+
+  it('should return an empty array when the file name has no uppercase characters, even if the containing folder has uppercase characters', () => {
+    const filePath = '/code/SAS Projects/my_sas_file.sas'
+    expect(lowerCaseFileNames.test(filePath)).toEqual([])
+  })
+
+  it('should return an array with a single diagnostic when the file name has uppercase characters', () => {
+    const filePath = '/code/sas/my SAS file.sas'
+    expect(lowerCaseFileNames.test(filePath)).toEqual([
+      {
+        message: 'File name contains uppercase characters',
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+})

src/rules/lowerCaseFileNames.ts

@@ -0,0 +1,32 @@
+import { PathLintRule } from '../types/LintRule'
+import { LintRuleType } from '../types/LintRuleType'
+import { Severity } from '../types/Severity'
+import path from 'path'
+
+const name = 'lowerCaseFileNames'
+const description = 'Enforce the use of lower case file names.'
+const message = 'File name contains uppercase characters'
+const test = (value: string) => {
+  const fileName = path.basename(value)
+  if (fileName.toLocaleLowerCase() === fileName) return []
+  return [
+    {
+      message,
+      lineNumber: 1,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    }
+  ]
+}
+
+/**
+ * Lint rule that checks for the absence of uppercase characters in a given file name.
+ */
+export const lowerCaseFileNames: PathLintRule = {
+  type: LintRuleType.Path,
+  name,
+  description,
+  message,
+  test
+}

src/rules/maxLineLength.spec.ts

@@ -0,0 +1,44 @@
+import { LintConfig, Severity } from '../types'
+import { maxLineLength } from './maxLineLength'
+
+describe('maxLineLength', () => {
+  it('should return an empty array when the line is within the specified length', () => {
+    const line = "%put 'hello';"
+    const config = new LintConfig({ maxLineLength: 60 })
+    expect(maxLineLength.test(line, 1, config)).toEqual([])
+  })
+
+  it('should return an array with a single diagnostic when the line exceeds the specified length', () => {
+    const line = "%put 'hello';"
+    const config = new LintConfig({ maxLineLength: 10 })
+    expect(maxLineLength.test(line, 1, config)).toEqual([
+      {
+        message: `Line exceeds maximum length by 3 characters`,
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+
+  it('should fall back to a default of 80 characters', () => {
+    const line =
+      'Prow scuttle parrel provost Sail ho shrouds spirits boom mizzenmast yardarm. Pinnace holystone.'
+    expect(maxLineLength.test(line, 1)).toEqual([
+      {
+        message: `Line exceeds maximum length by 15 characters`,
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+
+  it('should return an empty array for lines within the default length', () => {
+    const line =
+      'Prow scuttle parrel provost Sail ho shrouds spirits boom mizzenmast yard'
+    expect(maxLineLength.test(line, 1)).toEqual([])
+  })
+})

src/rules/maxLineLength.ts

@@ -0,0 +1,32 @@
+import { LintConfig } from '../types'
+import { LineLintRule } from '../types/LintRule'
+import { LintRuleType } from '../types/LintRuleType'
+import { Severity } from '../types/Severity'
+
+const name = 'maxLineLength'
+const description = 'Restrict lines to the specified length.'
+const message = 'Line exceeds maximum length'
+const test = (value: string, lineNumber: number, config?: LintConfig) => {
+  const maxLineLength = config?.maxLineLength || 80
+  if (value.length <= maxLineLength) return []
+  return [
+    {
+      message: `${message} by ${value.length - maxLineLength} characters`,
+      lineNumber,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    }
+  ]
+}
+
+/**
+ * Lint rule that checks if a line has exceeded the configured maximum length.
+ */
+export const maxLineLength: LineLintRule = {
+  type: LintRuleType.Line,
+  name,
+  description,
+  message,
+  test
+}

src/rules/noSpacesInFileNames.ts

@@ -1,7 +1,7 @@
 import { PathLintRule } from '../types/LintRule'
 import { LintRuleType } from '../types/LintRuleType'
-import path from 'path'
 import { Severity } from '../types/Severity'
+import path from 'path'
 
 const name = 'noSpacesInFileNames'
 const description = 'Enforce the absence of spaces within file names.'

src/rules/noTabIndentation.spec.ts

@@ -0,0 +1,22 @@
+import { Severity } from '../types/Severity'
+import { noTabIndentation } from './noTabIndentation'
+
+describe('noTabs', () => {
+  it('should return an empty array when the line is not indented with a tab', () => {
+    const line = "%put 'hello';"
+    expect(noTabIndentation.test(line, 1)).toEqual([])
+  })
+
+  it('should return an array with a single diagnostic when the line is indented with a tab', () => {
+    const line = "\t%put 'hello';"
+    expect(noTabIndentation.test(line, 1)).toEqual([
+      {
+        message: 'Line is indented with a tab',
+        lineNumber: 1,
+        startColumnNumber: 1,
+        endColumnNumber: 1,
+        severity: Severity.Warning
+      }
+    ])
+  })
+})

src/rules/noTabIndentation.ts

@@ -0,0 +1,30 @@
+import { LineLintRule } from '../types/LintRule'
+import { LintRuleType } from '../types/LintRuleType'
+import { Severity } from '../types/Severity'
+
+const name = 'noTabs'
+const description = 'Disallow indenting with tabs.'
+const message = 'Line is indented with a tab'
+const test = (value: string, lineNumber: number) => {
+  if (!value.startsWith('\t')) return []
+  return [
+    {
+      message,
+      lineNumber,
+      startColumnNumber: 1,
+      endColumnNumber: 1,
+      severity: Severity.Warning
+    }
+  ]
+}
+
+/**
+ * Lint rule that checks if a given line of text is indented with a tab.
+ */
+export const noTabIndentation: LineLintRule = {
+  type: LintRuleType.Line,
+  name,
+  description,
+  message,
+  test
+}