feat: add manifest-based package installation detection

packagemanager/npm_test.go

@@ -121,3 +121,90 @@ func TestNpmParseCommand(t *testing.T) {
 		})
 	}
 }
+
+func TestNpmParseCommand_ManifestInstallation(t *testing.T) {
+	pm, err := NewNpmPackageManager(DefaultNpmPackageManagerConfig())
+	assert.NoError(t, err)
+
+	cases := []struct {
+		name              string
+		args              []string
+		expectedManifest  bool
+		expectedFiles     []string
+		expectedTargets   int
+	}{
+		{
+			name:              "npm install without args (bare install)",
+			args:              []string{"install"},
+			expectedManifest:  true,
+			expectedFiles:     []string{"package.json"},
+			expectedTargets:   0,
+		},
+		{
+			name:              "npm i without args (short form)",
+			args:              []string{"i"},
+			expectedManifest:  true,
+			expectedFiles:     []string{"package.json"},
+			expectedTargets:   0,
+		},
+		{
+			name:              "npm install with explicit package",
+			args:              []string{"install", "react"},
+			expectedManifest:  false,
+			expectedFiles:     nil,
+			expectedTargets:   1,
+		},
+		{
+			name:              "npm install with multiple packages",
+			args:              []string{"install", "react", "vue"},
+			expectedManifest:  false,
+			expectedFiles:     nil,
+			expectedTargets:   2,
+		},
+		{
+			name:              "npm install with flags but no packages",
+			args:              []string{"install", "--save-dev"},
+			expectedManifest:  true,
+			expectedFiles:     []string{"package.json"},
+			expectedTargets:   0,
+		},
+		{
+			name:              "npm install with mixed args",
+			args:              []string{"install", "react", "--save"},
+			expectedManifest:  false,
+			expectedFiles:     nil,
+			expectedTargets:   1,
+		},
+		{
+			name:              "non-install command",
+			args:              []string{"run", "build"},
+			expectedManifest:  false,
+			expectedFiles:     nil,
+			expectedTargets:   0,
+		},
+		{
+			name:              "pnpm install without args",
+			args:              []string{"install"},
+			expectedManifest:  true,
+			expectedFiles:     []string{"package.json"},
+			expectedTargets:   0,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			parsed, err := pm.ParseCommand(tc.args)
+			assert.NoError(t, err)
+			
+			assert.Equal(t, tc.expectedManifest, parsed.IsManifestInstall, "IsManifestInstall mismatch")
+			assert.Equal(t, tc.expectedFiles, parsed.ManifestFiles, "ManifestFiles mismatch")
+			assert.Equal(t, tc.expectedTargets, len(parsed.InstallTargets), "InstallTargets count mismatch")
+			
+			// Test helper methods
+			assert.Equal(t, tc.expectedManifest, parsed.HasManifestInstall(), "HasManifestInstall mismatch")
+			
+			expectedShouldExtract := tc.expectedManifest && tc.expectedTargets == 0
+			assert.Equal(t, expectedShouldExtract, parsed.ShouldExtractFromManifest(), "ShouldExtractFromManifest mismatch")
+		})
+	}
+}