1 // Copyright 2022 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package covcmd 6 7 import ( 8 "crypto/sha256" 9 "fmt" 10 "internal/coverage" 11 ) 12 13 // CoverPkgConfig is a bundle of information passed from the Go 14 // command to the cover command during "go build -cover" runs. The 15 // Go command creates and fills in a struct as below, then passes 16 // file containing the encoded JSON for the struct to the "cover" 17 // tool when instrumenting the source files in a Go package. 18 type CoverPkgConfig struct { 19 // File into which cmd/cover should emit summary info 20 // when instrumentation is complete. 21 OutConfig string 22 23 // Import path for the package being instrumented. 24 PkgPath string 25 26 // Package name. 27 PkgName string 28 29 // Instrumentation granularity: one of "perfunc" or "perblock" (default) 30 Granularity string 31 32 // Module path for this package (empty if no go.mod in use) 33 ModulePath string 34 35 // Local mode indicates we're doing a coverage build or test of a 36 // package selected via local import path, e.g. "./..." or 37 // "./foo/bar" as opposed to a non-relative import path. See the 38 // corresponding field in cmd/go's PackageInternal struct for more 39 // info. 40 Local bool 41 42 // EmitMetaFile if non-empty is the path to which the cover tool should 43 // directly emit a coverage meta-data file for the package, if the 44 // package has any functions in it. The go command will pass in a value 45 // here if we've been asked to run "go test -cover" on a package that 46 // doesn't have any *_test.go files. 47 EmitMetaFile string 48 } 49 50 // CoverFixupConfig contains annotations/notes generated by the 51 // cmd/cover tool (during instrumentation) to be passed on to the 52 // compiler when the instrumented code is compiled. The cmd/cover tool 53 // creates a struct of this type, JSON-encodes it, and emits the 54 // result to a file, which the Go command then passes to the compiler 55 // when the instrumented package is built. 56 type CoverFixupConfig struct { 57 // Name of the variable (created by cmd/cover) containing the 58 // encoded meta-data for the package. 59 MetaVar string 60 61 // Length of the meta-data. 62 MetaLen int 63 64 // Hash computed by cmd/cover of the meta-data. 65 MetaHash string 66 67 // Instrumentation strategy. For now this is always set to 68 // "normal", but in the future we may add new values (for example, 69 // if panic paths are instrumented, or if the instrumenter 70 // eliminates redundant counters). 71 Strategy string 72 73 // Prefix assigned to the names of counter variables generated 74 // during instrumentation by cmd/cover. 75 CounterPrefix string 76 77 // Name chosen for the package ID variable generated during 78 // instrumentation. 79 PkgIdVar string 80 81 // Counter mode (e.g. set/count/atomic) 82 CounterMode string 83 84 // Counter granularity (perblock or perfunc). 85 CounterGranularity string 86 } 87 88 // MetaFileForPackage returns the expected name of the meta-data file 89 // for the package whose import path is 'importPath' in cases where 90 // we're using meta-data generated by the cover tool, as opposed to a 91 // meta-data file created at runtime. 92 func MetaFileForPackage(importPath string) string { 93 var r [32]byte 94 sum := sha256.Sum256([]byte(importPath)) 95 copy(r[:], sum[:]) 96 return coverage.MetaFilePref + fmt.Sprintf(".%x", r) 97 } 98