cue/load: remove some unused code

As found by staticcheck; these seem to have never been used.

Change-Id: I698aa9db61a17ed5addcae20e7e8dfd69c436157
Signed-off-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/536098
Reviewed-by: Roger Peppe <rogpeppe@gmail.com>
Unity-Result: CUEcueckoo <cueckoo@cuelang.org>
TryBot-Result: CUEcueckoo <cueckoo@cuelang.org>

Author: mvdan

cue/load/config.go

@@ -19,7 +19,6 @@ import (
 	"os"
 	pathpkg "path"
 	"path/filepath"
-	goruntime "runtime"
 	"strings"
 
 	"cuelang.org/go/cue/ast"
@@ -629,13 +628,3 @@ func (c Config) findRoot(dir string) string {
 		abs = d
 	}
 }
-
-func home() string {
-	env := "HOME"
-	if goruntime.GOOS == "windows" {
-		env = "USERPROFILE"
-	} else if goruntime.GOOS == "plan9" {
-		env = "home"
-	}
-	return os.Getenv(env)
-}

cue/load/errors.go

@@ -24,23 +24,6 @@ import (
 	"cuelang.org/go/cue/token"
 )
 
-func lastError(p *build.Instance) *PackageError {
-	if p == nil {
-		return nil
-	}
-	switch v := p.Err.(type) {
-	case *PackageError:
-		return v
-	}
-	return nil
-}
-
-func report(p *build.Instance, err *PackageError) {
-	if err != nil {
-		p.ReportError(err)
-	}
-}
-
 // A PackageError describes an error loading information about a package.
 type PackageError struct {
 	ImportStack    []string  // shortest path from package named on command line to this one

cue/load/loader.go

@@ -23,7 +23,6 @@ import (
 	pathpkg "path"
 	"path/filepath"
 	"strings"
-	"unicode"
 
 	"cuelang.org/go/cue/ast"
 	"cuelang.org/go/cue/build"
@@ -257,63 +256,3 @@ func (s *importStack) Pop() {
 func (s *importStack) Copy() []string {
 	return append([]string{}, *s...)
 }
-
-// shorterThan reports whether sp is shorter than t.
-// We use this to record the shortest import sequences
-// that leads to a particular package.
-func (sp *importStack) shorterThan(t []string) bool {
-	s := *sp
-	if len(s) != len(t) {
-		return len(s) < len(t)
-	}
-	// If they are the same length, settle ties using string ordering.
-	for i := range s {
-		if s[i] != t[i] {
-			return s[i] < t[i]
-		}
-	}
-	return false // they are equal
-}
-
-// reusePackage reuses package p to satisfy the import at the top
-// of the import stack stk. If this use causes an import loop,
-// reusePackage updates p's error information to record the loop.
-func (l *loader) reusePackage(p *build.Instance) *build.Instance {
-	// We use p.Internal.Imports==nil to detect a package that
-	// is in the midst of its own loadPackage call
-	// (all the recursion below happens before p.Internal.Imports gets set).
-	if p.ImportPaths == nil {
-		if err := lastError(p); err == nil {
-			err = l.errPkgf(nil, "import cycle not allowed")
-			err.IsImportCycle = true
-			report(p, err)
-		}
-		p.Incomplete = true
-	}
-	// Don't rewrite the import stack in the error if we have an import cycle.
-	// If we do, we'll lose the path that describes the cycle.
-	if err := lastError(p); err != nil && !err.IsImportCycle && l.stk.shorterThan(err.ImportStack) {
-		err.ImportStack = l.stk.Copy()
-	}
-	return p
-}
-
-// dirToImportPath returns the pseudo-import path we use for a package
-// outside the CUE path. It begins with _/ and then contains the full path
-// to the directory. If the package lives in c:\home\gopher\my\pkg then
-// the pseudo-import path is _/c_/home/gopher/my/pkg.
-// Using a pseudo-import path like this makes the ./ imports no longer
-// a special case, so that all the code to deal with ordinary imports works
-// automatically.
-func dirToImportPath(dir string) string {
-	return pathpkg.Join("_", strings.Map(makeImportValid, filepath.ToSlash(dir)))
-}
-
-func makeImportValid(r rune) rune {
-	// Should match Go spec, compilers, and ../../go/parser/parser.go:/isValidImport.
-	const illegalChars = `!"#$%&'()*,:;<=>?[\]^{|}` + "`\uFFFD"
-	if !unicode.IsGraphic(r) || unicode.IsSpace(r) || strings.ContainsRune(illegalChars, r) {
-		return '_'
-	}
-	return r
-}