fix(lambda): save params before running sam command when --watch is selected (#6089)

## Problem
When --watch flag is used, the sync process remains alive. The region
and stack_name info get written to config file only after the process
finishes. This means customer would not be able to see (or refresh) the
latest deployed resoures during the sync process.

## Solution
Write to samconfig.toml before running sam sync

---

<!--- REMINDER: Ensure that your PR meets the guidelines in
CONTRIBUTING.md -->

License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: mbfreder

packages/core/src/shared/sam/sync.ts

@@ -354,9 +354,15 @@ export async function runSamSync(args: SyncParams) {
         }),
     })
 
-    await runInTerminal(sam, 'sync')
+    // with '--watch' selected, the sync process will run in the background until the user manually kills it
+    // we need to save the stack and region to the samconfig file now, otherwise the user would not see latest deployed resoure during this sync process
     const { paramsSource, stackName, region, projectRoot } = args
     const shouldWriteSyncSamconfigGlobal = paramsSource !== ParamsSource.SamConfig && !!stackName && !!region
+    if (boundArgs.includes('--watch')) {
+        shouldWriteSyncSamconfigGlobal && (await writeSamconfigGlobal(projectRoot, stackName, region))
+    }
+
+    await runInTerminal(sam, 'sync')
     shouldWriteSyncSamconfigGlobal && (await writeSamconfigGlobal(projectRoot, stackName, region))
 }
 

packages/core/src/test/shared/sam/sync.test.ts

@@ -1030,6 +1030,91 @@ describe('SAM runSync', () => {
             prompterTester.assertCallAll()
         })
 
+        it('[entry: command palette] specify and save flag (with --watch) should save params before starting SAM process', async () => {
+            const prompterTester = PrompterTester.init()
+                .handleQuickPick('Select a SAM/CloudFormation Template', async (quickPick) => {
+                    // Need sometime to wait for the template to search for template file
+                    await quickPick.untilReady()
+                    assert.strictEqual(quickPick.items[0].label, templateFile.fsPath)
+                    quickPick.acceptItem(quickPick.items[0])
+                })
+                .handleQuickPick('Specify parameter source for sync', async (picker) => {
+                    // Need time to check samconfig.toml file and generate options
+                    await picker.untilReady()
+                    assert.strictEqual(picker.items[0].label, 'Specify required parameters and save as defaults')
+                    picker.acceptItem(picker.items[0])
+                })
+                .handleQuickPick('Select a region', (quickPick) => {
+                    const select = quickPick.items.filter((i) => i.detail === 'us-west-2')[0]
+                    quickPick.acceptItem(select || quickPick.items[0])
+                })
+                .handleQuickPick('Select a CloudFormation Stack', async (picker) => {
+                    await picker.untilReady()
+                    assert.strictEqual(picker.items[2].label, 'stack3')
+                    picker.acceptItem(picker.items[2])
+                })
+                .handleQuickPick('Specify S3 bucket for deployment artifacts', async (picker) => {
+                    await picker.untilReady()
+                    assert.strictEqual(picker.items.length, 2)
+                    assert.strictEqual(picker.items[0].label, 'Create a SAM CLI managed S3 bucket')
+                    picker.acceptItem(picker.items[0])
+                })
+                .handleQuickPick('Specify parameters for sync', async (picker) => {
+                    await picker.untilReady()
+                    assert.strictEqual(picker.items.length, 9)
+                    const dependencyLayer = picker.items.filter((item) => item.label === 'Dependency layer')[0]
+                    const useContainer = picker.items.filter((item) => item.label === 'Use container')[0]
+                    const watch = picker.items.filter((item) => item.label === 'Watch')[0]
+                    picker.acceptItems(dependencyLayer, useContainer, watch)
+                })
+                .build()
+
+            // Invoke sync command from command palette
+            await runSync('code', undefined)
+
+            assert(mockGetSamCliPath.calledOnce)
+            assert(mockChildProcessClass.calledOnce)
+            assert.deepEqual(mockChildProcessClass.getCall(0).args, [
+                'sam-cli-path',
+                [
+                    'sync',
+                    '--code',
+                    '--template',
+                    `${templateFile.fsPath}`,
+                    '--stack-name',
+                    'stack3',
+                    '--region',
+                    'us-west-2',
+                    '--no-dependency-layer',
+                    '--save-params',
+                    '--dependency-layer',
+                    '--use-container',
+                    '--watch',
+                ],
+                {
+                    spawnOptions: {
+                        cwd: projectRoot?.fsPath,
+                        env: {
+                            AWS_TOOLING_USER_AGENT: 'AWS-Toolkit-For-VSCode/testPluginVersion',
+                            SAM_CLI_TELEMETRY: '0',
+                        },
+                    },
+                },
+            ])
+            assert(mockGetSpawnEnv.calledOnce)
+            assert(spyRunInterminal.calledOnce)
+            assert.deepEqual(spyRunInterminal.getCall(0).args, [mockSamSyncChildProcess, 'sync'])
+            assert.strictEqual(spyWriteSamconfigGlobal.callCount, 2)
+            assert(spyWriteSamconfigGlobal.calledBefore(spyRunInterminal))
+            // Check telementry
+            assertTelemetry('sam_sync', { result: 'Succeeded', source: undefined })
+            assertTelemetryCurried('sam_sync')({
+                syncedResources: 'CodeOnly',
+                source: undefined,
+            })
+            prompterTester.assertCallAll()
+        })
+
         it('[entry: template file] specify flag should instantiate correct process in terminal', async () => {
             const prompterTester = PrompterTester.init()
                 .handleQuickPick('Specify parameter source for sync', async (picker) => {

packages/toolkit/.changes/next-release/Bug Fix-399d3f79-390e-4892-8cf5-e4a189860334.json

@@ -0,0 +1,4 @@
+{
+	"type": "Bug Fix",
+	"description": "appBuilder refresh feature doesnt work during sync --watch"
+}