Awesome
go-callsite-stats: analyse function callsites
Useful for refactoring, better naming, better signatures, OOP
go install github.com/nikolaydubina/go-callsite-stats@latest
go-callsite-stats ./...
Output format
x<number of function calls>: <var name>:<count>,<var name>:<count> = <func name>(<arg name>:<count>, <arg name>:<count>)
Example Kubernetes
x16: (no assignments) = execHostnameTest(serviceAddress:7)
(nodePortAddress:3)
(nodePortAddress0:3)
(nodePortAddress1:2)
(clusterIPAddress:1)
x16: pod:10, err:12 = CreatePod(client:11, namespace:10, nil:9, pvclaims:6, false:7, execCommand:2)
clientPod:1 (c:2, ns:2, podCount:2, true:3)
_:1 (pod:1, pod:1, pvclaims:2, false:2)
err:1 (ctx:1, nil:1, createdClaims:1, pvcClaims:1)
(namespace:1, nameSpace:1, podTemplate:1)
(, basePod:1)
x16: (no assignments) = GET()
x16: deployment:11, err:14 = UpdateDeploymentWithRetries(c:14, ns:14, deploymentName:3, applyUpdate:1, poll:1,pollShortTimeout:1)
_:2 (client:1, namespace:1, pollTimeout:1)
deploymentWithUpdatedReplicas:1 (applyUpdate:1, pollInterval:1, name:1)
x16: err:16 = waitForDefinition(schemaFoo:12
(schemaWaldo:3)
(expect:1)
go-callsite-stats -json ./...
{"function_name":"AddReference","return_ignored_count":0,"argument_name_count":[{"name":1}],"multiple_assignment_count":0,"multiple_assignment_with_other_count":0}
{"function_name":"extractRawLog","return_ignored_count":0,"return_name_count":[{"err":1}],"multiple_assignment_count":1,"multiple_assignment_with_other_count":0}
{"function_name":"CreatePVC","return_ignored_count":0,"return_name_count":[{"err":3,"pvc":8,"pvclaim":14,"tmpClaim":1},{"err":23}],"argument_name_count":[{"c":6,"client":15,"cs":2,"ns":1,"pvc":2},{"namespace":15,"ns":8},{"claim":1,"pvc":6,"pvclaimSpec":1}],"multiple_assignment_count":26,"multiple_assignment_with_other_count":0}
{"function_name":"testNotReachableHTTP","return_ignored_count":0,"argument_name_count":[{"nodeIP":2,"tcpIngressIP":1},{"svcPort":1,"tcpNodePort":1,"tcpNodePortOld":1},{"loadBalancerLagTimeout":1}],"multiple_assignment_count":0,"multiple_assignment_with_other_count":0}
Select specific functions and reformat output
go-callsite-stats -json ./... | grep createEndpoint | jq
{
"function_name": "createEndpoint",
"call_count": 1,
"argument_name_count": [
{
"i": 1
}
],
"return_name_count": [
{
"mu": 1
},
{
"listener": 1
},
{
"serverURL": 1
},
{
"endpoint": 1
},
{
"err": 1
}
],
"return_ignored_count": 0,
"multiple_assignment_count": 1,
"multiple_assignment_with_other_count": 0
}
Further Improvements
- skip build files and not include directives
- skip generated once go@1.21 is released
- asserting that type in methods in callsites matches target type
- filtering specific method receiver
- filtering specific declaration package name
- graph which other functions a function is called with in multiple assignments
- graph which other functions and fields a function is called in chain of call expression
- generated HTML nice visualization
- file and code location in UI
- file tree in UI
- website with open source analysis based on pkg.go.dev
Appendix A: why not go analysis toolchain
Go analysis toolchain does not support multiple packages in pass.
They recommend either export to STDOUT and process in separate process or to use go/packages.