From 90aacbc5b5ccfaa3d513c29339caeafbeb1ffeff Mon Sep 17 00:00:00 2001
From: actionless <actionless.loveless@gmail.com>
Date: Tue, 21 Apr 2020 19:51:11 +0200
Subject: [PATCH 1/3] fix(gears: matcher: default_matcher): handle sidecase of
 string.match-ing the empty string ('')

---
 lib/gears/matcher.lua | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/gears/matcher.lua b/lib/gears/matcher.lua
index a0ad4bb48..636eb7aa5 100644
--- a/lib/gears/matcher.lua
+++ b/lib/gears/matcher.lua
@@ -79,7 +79,13 @@ local matcher = {}
 -- @see remove_matching_source
 
 local function default_matcher(a, b)
-    return a == b or (type(a) == "string" and a:match(b))
+    local result = a == b
+    if result then return result end
+    if type(a) == "string" and type(b) == "string" then
+      result = a:match(b)
+      if result == '' then result = nil end
+    end
+    return result
 end
 
 local function greater_matcher(a, b)

From fa494a1e18569b4c61a34571e436d7e310d7bb38 Mon Sep 17 00:00:00 2001
From: actionless <actionless.loveless@gmail.com>
Date: Wed, 22 Apr 2020 01:40:00 +0200
Subject: [PATCH 2/3] test(spec: gears: matcher): spec _match() for string typ

---
 spec/gears/matcher_spec.lua | 46 +++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 spec/gears/matcher_spec.lua

diff --git a/spec/gears/matcher_spec.lua b/spec/gears/matcher_spec.lua
new file mode 100644
index 000000000..01969ec01
--- /dev/null
+++ b/spec/gears/matcher_spec.lua
@@ -0,0 +1,46 @@
+---------------------------------------------------------------------------
+-- @author Yauheni Kirylau
+-- @copyright 2020 Yauheni Kirylau
+---------------------------------------------------------------------------
+
+local matcher = require("gears.matcher")
+
+local matcher_instance = matcher()
+local test_obj = {
+    foo='bar',
+    spam='',
+}
+
+describe("gears.matcher", function()
+
+    describe("matching by normal string value", function()
+        local rule = {
+            foo='bar',
+        }
+        assert.is_true(matcher_instance:_match(test_obj, rule))
+    end)
+
+    describe("not matching by normal string value", function()
+        local rule = {
+            foo='nah',
+        }
+        assert.is_false(matcher_instance:_match(test_obj, rule))
+    end)
+
+    describe("matching by empty string value", function()
+        local rule = {
+            spam='',
+        }
+        assert.is_true(matcher_instance:_match(test_obj, rule))
+    end)
+
+    describe("not matching by empty string value", function()
+        local rule = {
+            foo='',
+        }
+        assert.is_false(matcher_instance:_match(test_obj, rule))
+    end)
+
+end)
+
+-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80

From f803347fc8a40aa3ba18c768dba7ee4efb6ff9ea Mon Sep 17 00:00:00 2001
From: actionless <actionless.loveless@gmail.com>
Date: Wed, 22 Apr 2020 01:52:41 +0200
Subject: [PATCH 3/3] fixup! fix(gears: matcher: default_matcher): handle
 sidecase of string.match-ing the empty string ('')

style: return true/false instead of assigning nil to result
---
 lib/gears/matcher.lua | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/gears/matcher.lua b/lib/gears/matcher.lua
index 636eb7aa5..c7a66ca2a 100644
--- a/lib/gears/matcher.lua
+++ b/lib/gears/matcher.lua
@@ -80,10 +80,10 @@ local matcher = {}
 
 local function default_matcher(a, b)
     local result = a == b
-    if result then return result end
+    if result then return true end
     if type(a) == "string" and type(b) == "string" then
       result = a:match(b)
-      if result == '' then result = nil end
+      if result == '' then return false end
     end
     return result
 end