feat: support disabling bundled mcp servers

tests/lib/mcp-config.test.js

@@ -0,0 +1,62 @@
+'use strict';
+
+const assert = require('assert');
+
+const { filterMcpConfig, parseDisabledMcpServers } = require('../../scripts/lib/mcp-config');
+
+function test(name, fn) {
+  try {
+    fn();
+    console.log(`  \u2713 ${name}`);
+    return true;
+  } catch (error) {
+    console.log(`  \u2717 ${name}`);
+    console.log(`    Error: ${error.message}`);
+    return false;
+  }
+}
+
+function runTests() {
+  console.log('\n=== Testing mcp-config.js ===\n');
+
+  let passed = 0;
+  let failed = 0;
+
+  if (test('parseDisabledMcpServers dedupes and trims values', () => {
+    assert.deepStrictEqual(
+      parseDisabledMcpServers(' github,exa ,github,,playwright '),
+      ['github', 'exa', 'playwright']
+    );
+  })) passed++; else failed++;
+
+  if (test('filterMcpConfig removes disabled servers and preserves others', () => {
+    const result = filterMcpConfig({
+      mcpServers: {
+        github: { command: 'npx' },
+        exa: { url: 'https://mcp.exa.ai/mcp' },
+        memory: { command: 'npx' },
+      },
+      _comments: { usage: 'demo' },
+    }, ['github', 'memory']);
+
+    assert.deepStrictEqual(result.removed, ['github', 'memory']);
+    assert.deepStrictEqual(Object.keys(result.config.mcpServers), ['exa']);
+    assert.deepStrictEqual(result.config._comments, { usage: 'demo' });
+  })) passed++; else failed++;
+
+  if (test('filterMcpConfig leaves config unchanged when no disabled servers are provided', () => {
+    const result = filterMcpConfig({
+      mcpServers: {
+        github: { command: 'npx' },
+      },
+    }, []);
+
+    assert.deepStrictEqual(result.removed, []);
+    assert.deepStrictEqual(Object.keys(result.config.mcpServers), ['github']);
+  })) passed++; else failed++;
+
+  console.log(`\nResults: Passed: ${passed}, Failed: ${failed}`);
+  process.exit(failed > 0 ? 1 : 0);
+}
+
+runTests();

tests/scripts/install-apply.test.js

@@ -7,6 +7,7 @@ const fs = require('fs');
 const os = require('os');
 const path = require('path');
 const { execFileSync } = require('child_process');
+const { applyInstallPlan } = require('../../scripts/lib/install/apply');
 
 const SCRIPT = path.join(__dirname, '..', '..', 'scripts', 'install-apply.js');
 
@@ -440,6 +441,80 @@ function runTests() {
     }
   })) passed++; else failed++;
 
+  if (test('filters copied mcp config files when ECC_DISABLED_MCPS is set', () => {
+    const tempDir = createTempDir('install-apply-mcp-');
+    const sourcePath = path.join(tempDir, '.mcp.json');
+    const destinationPath = path.join(tempDir, 'installed', '.mcp.json');
+    const installStatePath = path.join(tempDir, 'installed', 'ecc-install-state.json');
+    const previousValue = process.env.ECC_DISABLED_MCPS;
+
+    try {
+      fs.mkdirSync(path.dirname(sourcePath), { recursive: true });
+      fs.writeFileSync(sourcePath, JSON.stringify({
+        mcpServers: {
+          github: { command: 'npx' },
+          exa: { url: 'https://mcp.exa.ai/mcp' },
+          memory: { command: 'npx' },
+        },
+      }, null, 2));
+
+      process.env.ECC_DISABLED_MCPS = 'github,memory';
+
+      applyInstallPlan({
+        targetRoot: path.join(tempDir, 'installed'),
+        installStatePath,
+        statePreview: {
+          schemaVersion: 'ecc.install.v1',
+          installedAt: new Date().toISOString(),
+          target: {
+            id: 'test-install',
+            kind: 'project',
+            root: path.join(tempDir, 'installed'),
+            installStatePath,
+          },
+          request: {
+            profile: null,
+            modules: ['test-mcp'],
+            includeComponents: [],
+            excludeComponents: [],
+            legacyLanguages: [],
+            legacyMode: false,
+          },
+          resolution: {
+            selectedModules: ['test-mcp'],
+            skippedModules: [],
+          },
+          source: {
+            repoVersion: null,
+            repoCommit: null,
+            manifestVersion: 1,
+          },
+          operations: [],
+        },
+        operations: [{
+          kind: 'copy-file',
+          moduleId: 'test-mcp',
+          sourcePath,
+          sourceRelativePath: '.mcp.json',
+          destinationPath,
+          strategy: 'preserve-relative-path',
+          ownership: 'managed',
+          scaffoldOnly: false,
+        }],
+      });
+
+      const installed = readJson(destinationPath);
+      assert.deepStrictEqual(Object.keys(installed.mcpServers), ['exa']);
+    } finally {
+      if (previousValue === undefined) {
+        delete process.env.ECC_DISABLED_MCPS;
+      } else {
+        process.env.ECC_DISABLED_MCPS = previousValue;
+      }
+      cleanup(tempDir);
+    }
+  })) passed++; else failed++;
+
   if (test('reinstall does not duplicate managed hook entries', () => {
     const homeDir = createTempDir('install-apply-home-');
     const projectDir = createTempDir('install-apply-project-');