A VSCode extension that displays AST node counts for Go functions via CodeLens, helping you identify functions suitable for inline optimization.
Features
Real-time AST counting: Shows the number of AST nodes in each function as you type
Inline optimization hints: Highlights functions under the 80-node threshold that may be inlined by the Go compiler
Function call detection: Marks functions with calls using ~ prefix, indicating potential inlining uncertainty
Noinline directive support: Detects //go:noinline comments and optionally hides those functions
Configurable filtering: Customize which functions to display based on node count and call count
⚠️ Important Notice
This extension is for reference only. The AST node count shown is an approximation and may not perfectly match the compiler's internal cost model. To verify whether a function will actually be inlined, always check the output of:
go build -gcflags="-m -m"
Configuration
This extension contributes the following settings:
goAstCodeLens.debounceDelay (default: 1000): Delay in milliseconds before recalculating AST nodes after typing stops
goAstCodeLens.showOnlyInlineable (default: true): Only show CodeLens for functions with less than 80 AST nodes
goAstCodeLens.maxFuncCalls (default: 1): Maximum number of function calls allowed to show CodeLens (0 = no function calls allowed)
goAstCodeLens.showNoinline (default: false): Show CodeLens for functions with //go:noinline directive
Commands
Go AST CodeLens: Delete AST Counter Binary: Delete the compiled AST counter binary
Go AST CodeLens: Rebuild AST Counter Binary: Rebuild the AST counter binary
How It Works
The extension uses a Go helper program to parse your code and count AST nodes. The counting logic:
