fix(update-check): detect nix and linuxbrew installs on linux

.github/workflows/test-update-instructions.yml

@@ -115,3 +115,22 @@ jobs:
           output=$($HOME/.npm-global/lib/node_modules/@infisical/cli/bin/update-hint)
           echo "Output: $output"
           echo "$output" | grep -q "npm update -g @infisical/cli" || (echo "Expected npm instruction, got: $output" && exit 1)
+
+      # The runner has apt-get, so without install-source detection this falls
+      # through to the apt instruction. Asserting empty output is what makes
+      # this a real regression test for the nix case.
+      - name: Test nix path detection
+        run: |
+          mkdir -p $HOME/nix/store/abc123-infisical-0.0.1/bin
+          cp update-hint $HOME/nix/store/abc123-infisical-0.0.1/bin/update-hint
+          output=$($HOME/nix/store/abc123-infisical-0.0.1/bin/update-hint)
+          echo "Output: $output"
+          [ -z "$output" ] || (echo "Expected no instruction for nix, got: $output" && exit 1)
+
+      - name: Test linuxbrew path detection
+        run: |
+          mkdir -p $HOME/linuxbrew/.linuxbrew/bin
+          cp update-hint $HOME/linuxbrew/.linuxbrew/bin/update-hint
+          output=$($HOME/linuxbrew/.linuxbrew/bin/update-hint)
+          echo "Output: $output"
+          echo "$output" | grep -q "brew update" || (echo "Expected brew instruction, got: $output" && exit 1)

packages/util/check-for-update.go

@@ -407,6 +407,19 @@ func getUpdateInstructions(goos string, execPath string) string {
 		if isNpm {
 			return "To update, run: npm update -g @infisical/cli"
 		}
+		// Nix-managed binaries live in the immutable store. The system package
+		// manager did not install them and cannot update them, so stay quiet
+		// rather than print a command that will not work.
+		if strings.Contains(p, "/nix/store/") {
+			return ""
+		}
+		// Trailing slash so this matches the linuxbrew prefix directory in both
+		// the multi-user (/home/linuxbrew/.linuxbrew) and single-user
+		// (~/.linuxbrew) layouts, without classifying unrelated paths such as
+		// /opt/linuxbrew-tools as a Homebrew install.
+		if strings.Contains(p, "linuxbrew/") {
+			return "To update, run: brew update && brew upgrade infisical"
+		}
 		pkgManager := getLinuxPackageManager()
 		switch pkgManager {
 		case "apt-get":

packages/util/check-for-update_test.go

@@ -23,7 +23,8 @@ func TestGetUpdateInstructions(t *testing.T) {
 		goos        string
 		execPath    string
 		expected    string
-		expectEmpty bool // true means assert empty result (vs. skipping runtime-dependent cases)
+		expectEmpty bool   // true means assert empty result (vs. skipping runtime-dependent cases)
+		notExpected string // assert the result does NOT contain this, for paths that must not match a detector
 	}{
 		// darwin
 		{
@@ -96,6 +97,30 @@ func TestGetUpdateInstructions(t *testing.T) {
 			execPath: "/home/user/.npm-global/lib/node_modules/@infisical/cli/bin/infisical",
 			expected: "npm update -g @infisical/cli",
 		},
+		{
+			name:        "linux nix returns empty",
+			goos:        "linux",
+			execPath:    "/nix/store/abc123-infisical-0.41.90/bin/infisical",
+			expectEmpty: true,
+		},
+		{
+			name:     "linux linuxbrew",
+			goos:     "linux",
+			execPath: "/home/linuxbrew/.linuxbrew/bin/infisical",
+			expected: "brew update && brew upgrade infisical",
+		},
+		{
+			name:     "linux linuxbrew single-user prefix",
+			goos:     "linux",
+			execPath: "/home/user/.linuxbrew/bin/infisical",
+			expected: "brew update && brew upgrade infisical",
+		},
+		{
+			name:        "linux linuxbrew-tools is not a brew install",
+			goos:        "linux",
+			execPath:    "/opt/linuxbrew-tools/bin/infisical",
+			notExpected: "brew",
+		},
 	}
 
 	for _, tt := range tests {
@@ -107,6 +132,12 @@ func TestGetUpdateInstructions(t *testing.T) {
 				}
 				return
 			}
+			if tt.notExpected != "" {
+				if strings.Contains(result, tt.notExpected) {
+					t.Errorf("expected %q not to contain %q", result, tt.notExpected)
+				}
+				return
+			}
 			if tt.expected == "" {
 				return // skip runtime-dependent cases
 			}