In addition to Basic Completion and Smart Completion, which offer suggestions based on language semantics, you can use suggestions based on words used in the current file. To get this type of completion, press &shortcut:HippieCompletion; (Code | Completion | Cyclic Expand Word) and &shortcut:HippieBackwardCompletion; (Code | Completion | Cyclic Expand Word Backward).

GoLand tips, #2083