sourcegraph
diff --git a/cmd/src/version_check_test.go b/cmd/src/version_check_test.go
@@ -0,0 +1,77 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/sourcegraph/src-cli/internal/version"
+)
+
+func TestIsOutdated(t *testing.T) {
+	tests := []struct {
+		name         string
+		current      string
+		recommended  string
+		wantOutdated bool
+		wantOK       bool
+	}{
+		{"older patch", "4.3.0", "4.3.1", true, true},
+		{"older minor", "4.3.0", "4.4.0", true, true},
+		{"older major", "3.43.0", "4.0.0", true, true},
+		{"equal", "4.4.0", "4.4.0", false, true},
+		{"newer", "4.5.0", "4.4.0", false, true},
+		{"v-prefixed current", "v4.3.0", "4.4.0", true, true},
+		{"prerelease, same base, not outdated", "4.4.0-rc.1", "4.4.0", false, true},
+		{"prerelease, older base, outdated", "4.3.0-rc.1", "4.4.0", true, true},
+		{"unparseable current", "dev", "4.4.0", false, false},
+		{"empty recommended", "4.3.0", "", false, false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotOutdated, gotOK := isOutdated(tt.current, tt.recommended)
+			if gotOutdated != tt.wantOutdated || gotOK != tt.wantOK {
+				t.Errorf("isOutdated(%q, %q) = (%v, %v), want (%v, %v)",
+					tt.current, tt.recommended, gotOutdated, gotOK, tt.wantOutdated, tt.wantOK)
+			}
+		})
+	}
+}
+
+func TestShouldSkipVersionCheck(t *testing.T) {
+	// pretend this is a real release build for the duration of the test, since the
+	// default BuildTag ("dev") would otherwise short-circuit every case.
+	orig := version.BuildTag
+	version.BuildTag = "4.3.0"
+	t.Cleanup(func() { version.BuildTag = orig })
+
+	t.Run("skips for no-op subcommands", func(t *testing.T) {
+		for _, sub := range []string{"", "help", "version", "-h", "--help"} {
+			if !shouldSkipVersionCheck(sub) {
+				t.Errorf("shouldSkipVersionCheck(%q) = false, want true", sub)
+			}
+		}
+	})
+
+	t.Run("runs for normal subcommands", func(t *testing.T) {
+		for _, sub := range []string{"search", "batch", "api"} {
+			if shouldSkipVersionCheck(sub) {
+				t.Errorf("shouldSkipVersionCheck(%q) = true, want false", sub)
+			}
+		}
+	})
+
+	t.Run("skips when opt-out env var is set", func(t *testing.T) {
+		t.Setenv(envSkipVersionCheck, "1")
+		if !shouldSkipVersionCheck("search") {
+			t.Errorf("shouldSkipVersionCheck with %s set = false, want true", envSkipVersionCheck)
+		}
+	})
+
+	t.Run("skips for dev builds", func(t *testing.T) {
+		version.BuildTag = version.DefaultBuildTag
+		defer func() { version.BuildTag = "4.3.0" }()
+		if !shouldSkipVersionCheck("search") {
+			t.Error("shouldSkipVersionCheck for dev build = false, want true")
+		}
+	})
+}