Add no-submodule-imports rule

.vscode/settings.json

@@ -22,5 +22,6 @@
     },
 
     // Always use project's provided typescript compiler version
-    "typescript.tsdk": "node_modules/typescript/lib"
+    "typescript.tsdk": "node_modules/typescript/lib",
+    "files.eol": "\n"
 }

src/configs/all.ts

@@ -117,6 +117,7 @@ export const rules = {
     "no-string-literal": true,
     "no-string-throw": true,
     "no-sparse-arrays": true,
+    "no-submodule-imports": true,
     "no-unbound-method": true,
     "no-unsafe-any": true,
     "no-unsafe-finally": true,

src/rules/noSubmoduleImportsRule.ts

@@ -0,0 +1,115 @@
+/**
+ * @license
+ * Copyright 2017 Palantir Technologies, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import {
+    isCallExpression,
+    isExternalModuleReference,
+    isIdentifier,
+    isImportDeclaration,
+    isImportEqualsDeclaration,
+    isTextualLiteral,
+} from "tsutils";
+import * as ts from "typescript";
+import * as Lint from "../index";
+
+export class Rule extends Lint.Rules.AbstractRule {
+    /* tslint:disable:object-literal-sort-keys */
+    public static metadata: Lint.IRuleMetadata = {
+        ruleName: "no-submodule-imports",
+        description: Lint.Utils.dedent`
+            Disallows importing any submodule.`,
+        rationale: Lint.Utils.dedent`
+            Submodules of some packages are treated as private APIs and the import
+            paths may change without deprecation periods. It's best to stick with
+            top-level package exports.`,
+        optionsDescription: "A list of packages whose submodules are whitelisted.",
+        options: {
+            type: "array",
+            items: {
+                type: "string",
+            },
+            minLength: 0,
+        },
+        optionExamples: [true, [true, "rxjs", "@angular/core"]],
+        type: "functionality",
+        typescriptOnly: false,
+    };
+
+    public static FAILURE_STRING = "Submodule import paths from this package are disallowed; import from the root instead";
+
+    public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
+        return this.applyWithWalker(new NoSubmoduleImportsWalker(sourceFile, this.ruleName, this.ruleArguments));
+    }
+}
+
+class NoSubmoduleImportsWalker extends Lint.AbstractWalker<string[]> {
+    public walk(sourceFile: ts.SourceFile) {
+        const findDynamicImport = (node: ts.Node): void => {
+            if (isCallExpression(node) && node.arguments.length === 1 &&
+                (isIdentifier(node.expression) && node.expression.text === "require" ||
+                node.expression.kind === ts.SyntaxKind.ImportKeyword)) {
+                this.checkForBannedImport(node.arguments[0]);
+            }
+            return ts.forEachChild(node, findDynamicImport);
+        };
+
+        for (const statement of sourceFile.statements) {
+            if (isImportDeclaration(statement)) {
+                this.checkForBannedImport(statement.moduleSpecifier);
+            } else if (isImportEqualsDeclaration(statement)) {
+                if (isExternalModuleReference(statement.moduleReference) && statement.moduleReference.expression !== undefined) {
+                    this.checkForBannedImport(statement.moduleReference.expression);
+                }
+            } else {
+                ts.forEachChild(statement, findDynamicImport);
+            }
+        }
+    }
+
+    private checkForBannedImport(expression: ts.Expression) {
+        if (isTextualLiteral(expression)) {
+            if (isAbsoluteOrRelativePath(expression.text) || !isSubmodulePath(expression.text)) {
+                return;
+            }
+
+            /**
+             * A submodule is being imported.
+             * Check if its path contains any
+             * of the whitelist packages.
+             */
+            for (const option of this.options) {
+                if (expression.text.startsWith(`${option}/`)) {
+                    return;
+                }
+            }
+
+            this.addFailureAtNode(expression, Rule.FAILURE_STRING);
+        }
+    }
+}
+
+function isAbsoluteOrRelativePath(path: string): boolean {
+    return /^(..?(\/|$)|\/)/.test(path);
+}
+
+function isScopedPath(path: string): boolean {
+    return path[0] === "@";
+}
+
+function isSubmodulePath(path: string): boolean {
+    return path.split("/").length > (isScopedPath(path) ? 2 : 1);
+}

test/rules/no-submodule-imports/dynamic-imports/test.ts.lint

@@ -0,0 +1,23 @@
+const dynamicImport = import "lodash";
+
+const dynamicImport = import "lodash/sub-module";
+                             ~~~~~~~~~~~~~~~~~~~ [0]
+
+const dynamicImport = import "lodash/a/b/c/sub-module";
+                             ~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+
+const dynamicImport = import "@blueprintjs/core";
+
+const dynamicImport = import "@blueprintjs/core/sub-module";
+                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+const dynamicImport = import "@blueprintjs/core/a/b/c/sub-module";
+                             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+const dynamicImport = import "rxjs";
+const dynamicImport = import "rxjs/sub-module";
+const dynamicImport = import "@angular/core";
+const dynamicImport = import "@angular/core/forms/directives";
+
+[0]: Submodule import paths from this package are disallowed; import from the root instead

test/rules/no-submodule-imports/dynamic-imports/tslint.json

@@ -0,0 +1,5 @@
+{
+  "rules": {
+    "no-submodule-imports": [true, "@angular/core", "rxjs"]
+  }
+}

test/rules/no-submodule-imports/static-imports/test.ts.lint

@@ -0,0 +1,61 @@
+import { submodule } from "@blueprintjs/core";
+
+import { submodule } from "@blueprintjs/core/sub-module";
+                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import submodule = require("@blueprintjs/core");
+
+import submodule = require("@blueprintjs/core/sub-module");
+                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import { submodule } from "@blueprintjs/core";
+
+import { submodule } from "@blueprintjs/core/a/b/c/sub-module";
+                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import submodule = require("@blueprintjs/core");
+
+import submodule = require("@blueprintjs/core/a/b/c/sub-module");
+                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import { submodule } from "@angular/core";
+import { submodule } from "@angular/core/sub-module";
+import submodule = require("@angular/core");
+import submodule = require("@angular/core/sub-module");
+import { submodule } from "@angular/core";
+import { submodule } from "@angular/core/a/b/c/sub-module";
+import submodule = require("@angular/core");
+import submodule = require("@angular/core/a/b/c/sub-module");
+
+
+import { submodule } from "lodash";
+
+import { submodule } from "lodash/sub-module";
+                          ~~~~~~~~~~~~~~~~~~~ [0]
+
+import submodule = require("lodash");
+
+import submodule = require("lodash/sub-module");
+                           ~~~~~~~~~~~~~~~~~~~ [0]
+
+import { submodule } from "lodash";
+
+import { submodule } from "lodash/a/b/c/sub-module";
+                          ~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import submodule = require("lodash");
+
+import submodule = require("lodash/a/b/c/sub-module");
+                           ~~~~~~~~~~~~~~~~~~~~~~~~~ [0]
+
+import { submodule } from "rxjs";
+import { submodule } from "rxjs/sub-module";
+import submodule = require("rxjs");
+import submodule = require("rxjs/sub-module");
+import { submodule } from "rxjs";
+import { submodule } from "rxjs/a/b/c/sub-module";
+import submodule = require("rxjs");
+import submodule = require("rxjs/a/b/c/sub-module");
+
+
+[0]: Submodule import paths from this package are disallowed; import from the root instead

test/rules/no-submodule-imports/static-imports/tslint.json

@@ -0,0 +1,5 @@
+{
+  "rules": {
+    "no-submodule-imports": [true, "@angular/core", "rxjs"]
+  }
+}