From 74e1e4965b96ba39fe582eb76b42dd3fb5ce238e Mon Sep 17 00:00:00 2001
From: Oleg Kovalov <oleg@hey.com>
Date: Thu, 3 Dec 2020 16:03:27 +0100
Subject: [PATCH 1/3] add bad defer unlock

---
 analyzer/testdata/src/extra/file.go  | 12 ++++++++++++
 analyzer/testdata/src/extra/rules.go |  9 +++++++++
 rules.go                             | 10 ++++++++++
 3 files changed, 31 insertions(+)

diff --git a/analyzer/testdata/src/extra/file.go b/analyzer/testdata/src/extra/file.go
index ef70f1df..ba31a83b 100644
--- a/analyzer/testdata/src/extra/file.go
+++ b/analyzer/testdata/src/extra/file.go
@@ -371,3 +371,15 @@ func mismatchingUnlock2Struct(x *withMutex, op func()) {
 	defer x.mu.Unlock()
 	op()
 }
+
+func mismatchingDeferLock1(x *withMutex, op func()) {
+	x.mu.Lock()
+	defer x.mu.Lock() // want `\Qmaybe defer x.mu.Unlock() was intended?`
+	op()
+}
+
+func mismatchingDeferLock2(x *withMutex, op func()) {
+	x.mu.RLock()
+	defer x.mu.RLock() // want `\Qmaybe defer x.mu.RUnlock() was intended?`
+	op()
+}
diff --git a/analyzer/testdata/src/extra/rules.go b/analyzer/testdata/src/extra/rules.go
index 994fb148..a9786e98 100644
--- a/analyzer/testdata/src/extra/rules.go
+++ b/analyzer/testdata/src/extra/rules.go
@@ -143,4 +143,13 @@ func _(m fluent.Matcher) {
 
 	m.Match(`$mu.Lock(); defer $mu.RUnlock()`).Report(`maybe $mu.RLock() was intended?`)
 	m.Match(`$mu.RLock(); defer $mu.Unlock()`).Report(`maybe $mu.Lock() was intended?`)
+
+	m.Match(`$mu1.Lock(); defer $mu2.Lock()`).
+		Where(m["mu1"].Text == m["mu2"].Text).
+		At(m["mu2"]).
+		Report(`maybe defer $mu1.Unlock() was intended?`)
+	m.Match(`$mu1.RLock(); defer $mu2.RLock()`).
+		Where(m["mu1"].Text == m["mu2"].Text).
+		At(m["mu2"]).
+		Report(`maybe defer $mu1.RUnlock() was intended?`)
 }
diff --git a/rules.go b/rules.go
index 69c13d2a..765b9bcd 100644
--- a/rules.go
+++ b/rules.go
@@ -396,6 +396,16 @@ func gocriticFlagDeref(m fluent.Matcher) {
 func gocriticBadLock(m fluent.Matcher) {
 	m.Match(`$mu.Lock(); defer $mu.RUnlock()`).Report(`maybe $mu.RLock() was intended?`)
 	m.Match(`$mu.RLock(); defer $mu.Unlock()`).Report(`maybe $mu.Lock() was intended?`)
+
+	// `mu1` and `mu2` are added to make possible report line were `m2` is used (with defer)
+	m.Match(`$mu1.Lock(); defer $mu2.Lock()`).
+		Where(m["mu1"].Text == m["mu2"].Text).
+		At(m["mu2"]).
+		Report(`maybe defer $mu1.Unlock() was intended?`)
+	m.Match(`$mu1.RLock(); defer $mu2.RLock()`).
+		Where(m["mu1"].Text == m["mu2"].Text).
+		At(m["mu2"]).
+		Report(`maybe defer $mu1.RUnlock() was intended?`)
 }
 
 func reviveBoolLiteralInExpr(m fluent.Matcher) {

From 56532936b75b6cecf1e0954302be9d52e1ca2bb1 Mon Sep 17 00:00:00 2001
From: Oleg Kovalov <oleg@hey.com>
Date: Thu, 3 Dec 2020 16:07:55 +0100
Subject: [PATCH 2/3] more tests

---
 analyzer/testdata/src/extra/negative_tests.go | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/analyzer/testdata/src/extra/negative_tests.go b/analyzer/testdata/src/extra/negative_tests.go
index a7491cae..c5517d20 100644
--- a/analyzer/testdata/src/extra/negative_tests.go
+++ b/analyzer/testdata/src/extra/negative_tests.go
@@ -20,6 +20,18 @@ func goodRUnlock(mu *sync.RWMutex, op func()) {
 	op()
 }
 
+func goodStrangeLocks(x1, x2 *sync.RWMutex, op func()) {
+	x1.Lock()
+	defer x2.Lock()
+	op()
+}
+
+func goodStrangeRLocks(x1, x2 *sync.RWMutex, op func()) {
+	x1.RLock()
+	defer x2.RLock()
+	op()
+}
+
 func differentMutexes(mu1, mu2 *sync.RWMutex, op func()) {
 	{
 		mu2.RLock()

From 8d06a78dbc8e489b9dbec8fc0972649398895180 Mon Sep 17 00:00:00 2001
From: Oleg Kovalov <oleg@hey.com>
Date: Thu, 3 Dec 2020 16:11:57 +0100
Subject: [PATCH 3/3] fix comment grammar

---
 rules.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rules.go b/rules.go
index 765b9bcd..e337921c 100644
--- a/rules.go
+++ b/rules.go
@@ -397,7 +397,7 @@ func gocriticBadLock(m fluent.Matcher) {
 	m.Match(`$mu.Lock(); defer $mu.RUnlock()`).Report(`maybe $mu.RLock() was intended?`)
 	m.Match(`$mu.RLock(); defer $mu.Unlock()`).Report(`maybe $mu.Lock() was intended?`)
 
-	// `mu1` and `mu2` are added to make possible report line were `m2` is used (with defer)
+	// `mu1` and `mu2` are added to make possible report a line where `m2` is used (with a defer)
 	m.Match(`$mu1.Lock(); defer $mu2.Lock()`).
 		Where(m["mu1"].Text == m["mu2"].Text).
 		At(m["mu2"]).