src/goDebugConfiguration: show warning that port is being used

This change needs to go in after the revert lands.

Updates #1729

Change-Id: I4ea882b69894143e7bc5353ca54b11112631cdf9
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/346270
Trust: Suzy Mueller <[email protected]>
Run-TryBot: Suzy Mueller <[email protected]>
TryBot-Result: kokoro <[email protected]>
Reviewed-by: Hyang-Ah Hana Kim <[email protected]>

Author: suzmue

src/goDebugConfiguration.ts

@@ -158,6 +158,12 @@ export class GoDebugConfigurationProvider implements vscode.DebugConfigurationPr
 			// for local mode, default to dlv-dap.
 			debugConfiguration['debugAdapter'] = debugConfiguration['mode'] !== 'remote' ? 'dlv-dap' : 'legacy';
 		}
+		if (debugConfiguration['debugAdapter'] === 'dlv-dap' && debugConfiguration['port']) {
+			this.showWarning(
+				'ignorePortUsedInDlvDapWarning',
+				"`port` is used with the 'dlv-dap' debugAdapter to support [launching the debug adapter server externally](https://github.com/golang/vscode-go/blob/master/docs/debugging.md#running-debugee-externally). Remove 'host' and 'port' from your launch.json if you are not launching a DAP server."
+			);
+		}
 		if (debugConfiguration['debugAdapter'] === 'dlv-dap' && debugConfiguration['mode'] === 'remote') {
 			this.showWarning(
 				'ignoreDlvDAPInRemoteModeWarning',