Reload from Disk vs. Invalidate Caches: Which Cache Layer Must Be Rebuilt After External Go Code Generation?

The Deterministic Choice for Correctness

When correctness is the priority and you must ensure that all externally generated symbols (via go generate or mock generators) are resolved, the team should standardize on File | Invalidate Caches / Restart. While expensive, this is the only operation that guarantees the disposal of stale index pointers and forces a complete rebuild of the symbol table from the current state of the disk.

Understanding the Cache Layers

To choose a policy, it is necessary to distinguish between the Virtual File System (VFS) and the Symbol Index:

• Virtual File System (VFS): This is the IDE's internal mirror of your files. Reload All from Disk updates the VFS. If the IDE knows a file exists but cannot find a function inside it, the VFS is likely current, but the index is not.
• Symbol Index: This is a pre-computed map of types, functions, and variables. Incremental indexing usually updates this when the VFS changes, but atomic-rename writes (common in many generators) can occasionally fail to trigger the necessary invalidation events, leaving the index pointing to non-existent or old offsets.

The Middle-Ground Workflow

To avoid full reindexing while maintaining symbol accuracy, implement this tiered escalation path:

1. Sync Dependencies: If go.mod or go.sum were changed externally (e.g., go mod tidy), click the "Sync Dependencies" notification or run the command from the Go tool window. This updates module resolution without a full cache wipe.
2. Reload All from Disk: Use this for simple file updates. If the file content is visible but symbols are red, move to step 3.
3. Invalidate Caches: Use this only when symbol resolution fails across the project after a major branch switch or large-scale code generation.

Verifying File-Watcher Limits

You can verify if your current GoLand build and OS environment are missing events by performing a "blind write" test:

# 1. Open a file in GoLand
# 2. In a terminal, overwrite the file using a method that bypasses standard watchers
echo "package main" > filename.go
# 3. Observe the IDE: if the content does not update within 5-10 seconds,
# your filesystem watcher is failing to detect the event.

Diagnostic Detail Needed: Are you using a network-mounted drive (NFS/Samba) or a Docker-mounted volume? If so, filesystem events are often not propagated, making Reload All from Disk mandatory and Invalidate Caches more frequent.