From 34bff378b31cef2e4e09934e1162c3b8b6707ca1 Mon Sep 17 00:00:00 2001
From: cherryblossom <31467609+cherryblossom000@users.noreply.github.com>
Date: Mon, 22 Jun 2020 23:48:23 +1000
Subject: [PATCH 1/3] fix(eslint-plugin): [no-namespace] allow namespaces in
 nested declarations with `allowDeclarations` (fixes #2237)

---
 .../eslint-plugin/docs/rules/no-namespace.md  |  8 ++++++
 .../eslint-plugin/src/rules/no-namespace.ts   | 10 ++++++-
 .../tests/rules/no-namespace.test.ts          | 26 +++++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/packages/eslint-plugin/docs/rules/no-namespace.md b/packages/eslint-plugin/docs/rules/no-namespace.md
index d82ad724b7b..b155c2aeb30 100644
--- a/packages/eslint-plugin/docs/rules/no-namespace.md
+++ b/packages/eslint-plugin/docs/rules/no-namespace.md
@@ -51,6 +51,14 @@ Examples of **correct** code for the `{ "allowDeclarations": true }` option:
 declare module 'foo' {}
 declare module foo {}
 declare namespace foo {}
+
+declare global {
+  namespace foo {}
+}
+
+declare module foo {
+  namespace foo {}
+}
 ```
 
 Examples of **incorrect** code for the `{ "allowDeclarations": false }` option:
diff --git a/packages/eslint-plugin/src/rules/no-namespace.ts b/packages/eslint-plugin/src/rules/no-namespace.ts
index 3698b4f941b..f8cc05b1047 100644
--- a/packages/eslint-plugin/src/rules/no-namespace.ts
+++ b/packages/eslint-plugin/src/rules/no-namespace.ts
@@ -50,6 +50,14 @@ export default util.createRule<Options, MessageIds>({
   create(context, [{ allowDeclarations, allowDefinitionFiles }]) {
     const filename = context.getFilename();
 
+    function isDeclaration(node: TSESTree.TSModuleDeclaration): boolean {
+      return (
+        node.declare === true ||
+        (node.parent!.parent?.type === AST_NODE_TYPES.TSModuleDeclaration &&
+          isDeclaration(node.parent!.parent))
+      );
+    }
+
     return {
       "TSModuleDeclaration[global!=true][id.type='Identifier']"(
         node: TSESTree.TSModuleDeclaration,
@@ -58,7 +66,7 @@ export default util.createRule<Options, MessageIds>({
           (node.parent &&
             node.parent.type === AST_NODE_TYPES.TSModuleDeclaration) ||
           (allowDefinitionFiles && util.isDefinitionFile(filename)) ||
-          (allowDeclarations && node.declare === true)
+          (allowDeclarations && isDeclaration(node))
         ) {
           return;
         }
diff --git a/packages/eslint-plugin/tests/rules/no-namespace.test.ts b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
index e175f5895df..901bea7354b 100644
--- a/packages/eslint-plugin/tests/rules/no-namespace.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
@@ -17,6 +17,32 @@ ruleTester.run('no-namespace', rule, {
       code: 'declare namespace foo {}',
       options: [{ allowDeclarations: true }],
     },
+    {
+      code: `
+declare global {
+  namespace foo {}
+}
+      `,
+      options: [{ allowDeclarations: true }],
+    },
+    {
+      code: `
+declare module foo {
+  namespace bar {}
+}
+      `,
+      options: [{ allowDeclarations: true }],
+    },
+    {
+      code: `
+declare global {
+  namespace foo {
+    namespace bar {}
+  }
+}
+      `,
+      options: [{ allowDeclarations: true }],
+    },
     {
       filename: 'test.d.ts',
       code: 'namespace foo {}',

From c532a95a7407d4eda20375d370ee46a3d8ade6cf Mon Sep 17 00:00:00 2001
From: cherryblossom <31467609+cherryblossom000@users.noreply.github.com>
Date: Tue, 23 Jun 2020 00:17:34 +1000
Subject: [PATCH 2/3] test(eslint-plugin): [no-namespace] add some more tests

---
 .../tests/rules/no-namespace.test.ts          | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/packages/eslint-plugin/tests/rules/no-namespace.test.ts b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
index 901bea7354b..80abf5dcf96 100644
--- a/packages/eslint-plugin/tests/rules/no-namespace.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
@@ -97,6 +97,28 @@ declare global {
         },
       ],
     },
+    {
+      code: 'module foo {}',
+      options: [{ allowDeclarations: true }],
+      errors: [
+        {
+          messageId: 'moduleSyntaxIsPreferred',
+          line: 1,
+          column: 1,
+        },
+      ],
+    },
+    {
+      code: 'namespace foo {}',
+      options: [{ allowDeclarations: true }],
+      errors: [
+        {
+          messageId: 'moduleSyntaxIsPreferred',
+          line: 1,
+          column: 1,
+        },
+      ],
+    },
     {
       code: 'declare module foo {}',
       errors: [

From 6d950947e9d7fd560fb887ffc0bd4cf497bf016d Mon Sep 17 00:00:00 2001
From: cherryblossom <31467609+cherryblossom000@users.noreply.github.com>
Date: Tue, 23 Jun 2020 00:20:00 +1000
Subject: [PATCH 3/3] test(eslint-plugin): [no-namespace] add another test

---
 .../eslint-plugin/tests/rules/no-namespace.test.ts     | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/packages/eslint-plugin/tests/rules/no-namespace.test.ts b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
index 80abf5dcf96..3bb9079b3fc 100644
--- a/packages/eslint-plugin/tests/rules/no-namespace.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-namespace.test.ts
@@ -39,6 +39,16 @@ declare global {
   namespace foo {
     namespace bar {}
   }
+}
+      `,
+      options: [{ allowDeclarations: true }],
+    },
+    {
+      code: `
+declare namespace foo {
+  namespace bar {
+    namespace baz {}
+  }
 }
       `,
       options: [{ allowDeclarations: true }],