From 3ba74b3195c3f4cc0d1fc78ffdabaa202f13db13 Mon Sep 17 00:00:00 2001
From: Fabian Homborg <FHomborg@gmail.com>
Date: Sun, 16 Sep 2018 13:03:15 +0200
Subject: [PATCH] [string] Match everything with an empty pattern and -e

I.e. `string match --entire "" -- banana` used to match nothing, now
it matches everything.

Fixes #4971.
---
 src/builtin_string.cpp | 3 ++-
 tests/string.err       | 3 +++
 tests/string.in        | 4 ++++
 tests/string.out       | 4 ++++
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/builtin_string.cpp b/src/builtin_string.cpp
index 2f765e02c..4f0834038 100644
--- a/src/builtin_string.cpp
+++ b/src/builtin_string.cpp
@@ -628,7 +628,8 @@ class wildcard_matcher_t : public string_matcher_t {
                 wcpattern[i] = towlower(wcpattern[i]);
             }
         }
-        if (opts.entire && !wcpattern.empty()) {
+        if (opts.entire) {
+            // If the pattern is empty, this becomes one ANY_STRING that matches everything.
             if (wcpattern.front() != ANY_STRING) wcpattern.insert(0, 1, ANY_STRING);
             if (wcpattern.back() != ANY_STRING) wcpattern.push_back(ANY_STRING);
         }
diff --git a/tests/string.err b/tests/string.err
index aebb82052..890f6a00c 100644
--- a/tests/string.err
+++ b/tests/string.err
@@ -283,6 +283,9 @@ string repeat -l fakearg
 ####################
 # string match --entire -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz
 
+####################
+# string match --entire "" -- banana
+
 ####################
 # string match -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz
 
diff --git a/tests/string.in b/tests/string.in
index e28f98bab..f267a1952 100644
--- a/tests/string.in
+++ b/tests/string.in
@@ -289,6 +289,10 @@ logmsg 'string match --entire -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abc
 string match --entire -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz
 or echo exit 1
 
+logmsg 'string match --entire "" -- banana'
+string match --entire "" -- banana
+or echo exit 1
+
 logmsg 'string match -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz'
 string match -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz
 or echo exit 1
diff --git a/tests/string.out b/tests/string.out
index 5fee2fbe1..d9de63114 100644
--- a/tests/string.out
+++ b/tests/string.out
@@ -384,6 +384,10 @@ kaabxz
 abbxy
 caabxyxz
 
+####################
+# string match --entire "" -- banana
+banana
+
 ####################
 # string match -r "a*b[xy]+" abc abxc bye aaabyz kaabxz abbxy abcx caabxyxz
 abx