From e234cf6dd57208a861eb4b711cdb456fdef47251 Mon Sep 17 00:00:00 2001
From: Joshua <josh.timmons@mongodb.com>
Date: Sat, 30 Nov 2024 00:13:56 -0500
Subject: [PATCH] Fix: ignore errs returned outside block (#25)

---
 .gitignore                       |  2 ++
 .golangci.yml                    |  7 -------
 spancheck.go                     | 20 ++++++++++++++++++
 testdata/enableall/enable_all.go | 36 ++++++++++++++++++++++++++++++++
 4 files changed, 58 insertions(+), 7 deletions(-)

diff --git a/.gitignore b/.gitignore
index 1f83be4..04b66d9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,3 +17,5 @@
 # Dependency directories (remove the comment below to include it)
 # vendor/
 src/
+
+.vscode
\ No newline at end of file
diff --git a/.golangci.yml b/.golangci.yml
index 15d8513..5d6ab12 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -17,7 +17,6 @@ linters:
     - errcheck
     - errname
     - errorlint
-    - exhaustive # checks exhaustiveness of enum switch statements
     - exportloopref # checks for pointers to enclosing loop variables
     - gci
     - gochecknoinits # checks that no init functions are present in Go code
@@ -59,12 +58,6 @@ linters-settings:
       - standard # Standard section: captures all standard packages.
       - default # Default section: contains all imports that could not be matched to another section type.
       - prefix(github.com/jjti)
-  exhaustive:
-    # Program elements to check for exhaustiveness.
-    # Default: [ switch ]
-    check:
-      - switch
-      - map
   gocritic:
     settings:
       captLocal:
diff --git a/spancheck.go b/spancheck.go
index 8fc7945..6b8b9fd 100644
--- a/spancheck.go
+++ b/spancheck.go
@@ -309,6 +309,11 @@ outer:
 			}
 			seen[b] = true
 
+			// Skip successors that are not nested within this current block.
+			if _, ok := nestedBlockTypes[b.Kind]; !ok {
+				continue
+			}
+
 			// Prune the search if the block uses v.
 			if blockUses(pass, b) {
 				continue
@@ -330,6 +335,21 @@ outer:
 	return search(defBlock.Succs)
 }
 
+var nestedBlockTypes = map[cfg.BlockKind]struct{}{
+	cfg.KindBody:            {},
+	cfg.KindForBody:         {},
+	cfg.KindForLoop:         {},
+	cfg.KindIfElse:          {},
+	cfg.KindIfThen:          {},
+	cfg.KindLabel:           {},
+	cfg.KindRangeBody:       {},
+	cfg.KindRangeLoop:       {},
+	cfg.KindSelectCaseBody:  {},
+	cfg.KindSelectAfterCase: {},
+	cfg.KindSwitchCaseBody:  {},
+	cfg.KindSwitchNextCase:  {},
+}
+
 // usesCall reports whether stmts contain a use of the selName call on variable v.
 func usesCall(
 	pass *analysis.Pass,
diff --git a/testdata/enableall/enable_all.go b/testdata/enableall/enable_all.go
index f60d68c..5ce6480 100644
--- a/testdata/enableall/enable_all.go
+++ b/testdata/enableall/enable_all.go
@@ -213,3 +213,39 @@ func testStartTrace() *trace.Span { // no error expected because this is in extr
 	_, span := trace.StartSpan(context.Background(), "bar")
 	return span
 }
+
+// https://github.com/jjti/go-spancheck/issues/25
+func _() error {
+	if true {
+		_, span := otel.Tracer("foo").Start(context.Background(), "bar")
+		span.End()
+	}
+
+	return errors.New("test")
+}
+
+func _() error {
+	if true {
+		_, span := otel.Tracer("foo").Start(context.Background(), "bar") // want "span.SetStatus is not called on all paths"
+		defer span.End()
+
+		if true {
+			span.RecordError(errors.New("test"))
+			return errors.New("test") // want "return can be reached without calling span.SetStatus"
+		}
+	}
+
+	return errors.New("test")
+}
+
+// TODO: the check below now fails after the change to fix issue 25 above.
+// func _() error {
+// 	var span *trace.Span
+
+// 	if true {
+// 		_, span = trace.StartSpan(context.Background(), "foo")
+// 		defer span.End()
+// 	}
+
+// 	return errors.New("test")
+// }