diff --git a/main.go b/main.go
index 5396fa4..824a3f2 100644
--- a/main.go
+++ b/main.go
@@ -972,6 +972,14 @@ func processImportCfg(flags []string) (newImportCfg string, _ error) {
 		impPath, pkgfile := pair[0], pair[1]
 		lpkg, err := listPackage(impPath)
 		if err != nil {
+			// TODO: it's unclear why an importcfg can include an import path
+			// that's not a dependency in an edge case with "go test ./...".
+			// See exporttest/*.go in testdata/scripts/test.txt.
+			// For now, spot the pattern and avoid the unnecessary error;
+			// the dependency is unused, so the packagefile line is redundant.
+			if strings.HasSuffix(curPkg.ImportPath, ".test]") && strings.HasPrefix(curPkg.ImportPath, impPath) {
+				continue
+			}
 			panic(err) // shouldn't happen
 		}
 		if lpkg.Name != "main" {
diff --git a/testdata/scripts/test.txt b/testdata/scripts/test.txt
index 2fb7f4b..ea87019 100644
--- a/testdata/scripts/test.txt
+++ b/testdata/scripts/test.txt
@@ -14,9 +14,18 @@ stdout 'package bar_test, func name:'
 
 [short] stop # no need to verify this with -short
 
-# also check that many packages test fine, including a main package and multiple
-# test packages
-garble test -v . ./somemain ./sometest
+# Also check that many packages test fine, including a main package and multiple
+# test packages.
+#
+# Exporttest is special, as it:
+#
+#  * uses an external test package
+#  * exports unexported APIs via export_test.go
+#  * is imported by another package, also tested via "./..."
+#
+# The combination of those used to result in "refusing to list non-dependency
+# package" errors, which we've currently worked around.
+garble test -v ./...
 stdout 'ok\s+test/bar\s'
 stdout 'PASS.*TestFoo'
 stdout 'PASS.*TestSeparateFoo'
@@ -26,6 +35,7 @@ stdout 'package bar_test, func name:'
 ! stdout 'OriginalFuncName'
 stdout '\?\s+test/bar/somemain\s'
 stdout 'ok\s+test/bar/sometest\s'
+stdout 'ok\s+test/bar/exporttest\s'
 
 # verify that non-build flags are kept
 garble test -withflag -v
@@ -47,6 +57,8 @@ package bar
 
 import "runtime"
 
+import _ "test/bar/exporttest"
+
 func LocalFoo() string { return "Foo" }
 
 var ImportedVar = "imported var value"
@@ -115,3 +127,17 @@ package sometest
 import "testing"
 
 func TestFoo(t *testing.T) {}
+-- exporttest/foo.go --
+package exporttest
+
+type foo int
+-- exporttest/export_test.go --
+package exporttest
+
+type Foo = foo
+-- exporttest/foo_test.go --
+package exporttest_test
+
+import "testing"
+
+func TestFoo(t *testing.T) {}