From 7224f22975c1615ee2e29cdd03b14559b42a94c6 Mon Sep 17 00:00:00 2001
From: Yuichi Nukiyama <oscar.wilde84@hotmail.co.jp>
Date: Sat, 23 Jul 2016 15:05:36 +0900
Subject: [PATCH 1/2] throw error when paths option mapping empty array

fix
---
 src/compiler/diagnosticMessages.json                  |  8 ++++++--
 src/compiler/program.ts                               |  3 +++
 tests/baselines/reference/pathsValidation3.errors.txt |  6 ++++++
 tests/baselines/reference/pathsValidation3.js         |  5 +++++
 tests/cases/compiler/pathsValidation3.ts              | 11 +++++++++++
 5 files changed, 31 insertions(+), 2 deletions(-)
 create mode 100644 tests/baselines/reference/pathsValidation3.errors.txt
 create mode 100644 tests/baselines/reference/pathsValidation3.js
 create mode 100644 tests/cases/compiler/pathsValidation3.ts

diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 8ffb02a8974..23018f3ef11 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2336,6 +2336,10 @@
         "category": "Error",
         "code": 5065
     },
+    "Substitutions for pattern '{0}' shouldn't be an empty array.": {
+        "category": "Error",
+        "code": 5066
+    },
     "Concatenate and emit output to single file.": {
         "category": "Message",
         "code": 6001
@@ -2800,11 +2804,11 @@
         "category": "Error",
         "code": 6133
     },
-    "Report errors on unused locals.": {
+    "Report errors on unused locals.": {
         "category": "Message",
         "code": 6134
     },
-    "Report errors on unused parameters.": {
+    "Report errors on unused parameters.": {
         "category": "Message",
         "code": 6135
     },
diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index 8d59c2d46fe..4b9948c3ba0 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -2200,6 +2200,9 @@ namespace ts {
                         programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Pattern_0_can_have_at_most_one_Asterisk_character, key));
                     }
                     if (isArray(options.paths[key])) {
+                        if (options.paths[key].length === 0) {
+                            programDiagnostics.add(createCompilerDiagnostic(Diagnostics.Substitutions_for_pattern_0_shouldn_t_be_an_empty_array, key));
+                        }
                         for (const subst of options.paths[key]) {
                             const typeOfSubst = typeof subst;
                             if (typeOfSubst === "string") {
diff --git a/tests/baselines/reference/pathsValidation3.errors.txt b/tests/baselines/reference/pathsValidation3.errors.txt
new file mode 100644
index 00000000000..3bb85203e6e
--- /dev/null
+++ b/tests/baselines/reference/pathsValidation3.errors.txt
@@ -0,0 +1,6 @@
+error TS5066: Substitutions for pattern 'foo' shouldn't be an empty array.
+
+
+!!! error TS5066: Substitutions for pattern 'foo' shouldn't be an empty array.
+==== tests/cases/compiler/a.ts (0 errors) ====
+    let x = 1;
\ No newline at end of file
diff --git a/tests/baselines/reference/pathsValidation3.js b/tests/baselines/reference/pathsValidation3.js
new file mode 100644
index 00000000000..bfffc647f63
--- /dev/null
+++ b/tests/baselines/reference/pathsValidation3.js
@@ -0,0 +1,5 @@
+//// [a.ts]
+let x = 1;
+
+//// [a.js]
+var x = 1;
diff --git a/tests/cases/compiler/pathsValidation3.ts b/tests/cases/compiler/pathsValidation3.ts
new file mode 100644
index 00000000000..8d677ed15b4
--- /dev/null
+++ b/tests/cases/compiler/pathsValidation3.ts
@@ -0,0 +1,11 @@
+// @filename: tsconfig.json
+{
+    "compilerOptions": {
+        "baseUrl": ".",
+        "paths": {
+            "foo": []
+        }
+    }
+}
+// @filename: a.ts
+let x = 1;
\ No newline at end of file

From bf2783f0c55e840a31642e087c9e6cb3d2ab41f1 Mon Sep 17 00:00:00 2001
From: Yuichi Nukiyama <oscar.wilde84@hotmail.co.jp>
Date: Sat, 23 Jul 2016 15:50:21 +0900
Subject: [PATCH 2/2] to run CI

---
 tests/cases/compiler/pathsValidation3.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tests/cases/compiler/pathsValidation3.ts b/tests/cases/compiler/pathsValidation3.ts
index 8d677ed15b4..28db959a881 100644
--- a/tests/cases/compiler/pathsValidation3.ts
+++ b/tests/cases/compiler/pathsValidation3.ts
@@ -7,5 +7,6 @@
         }
     }
 }
+
 // @filename: a.ts
 let x = 1;
\ No newline at end of file