feat: recursive sourcing of startup scripts

Author: d-led

common/nix_candidate_source.go

@@ -40,26 +40,48 @@ func (s *NixCandidateSource) WhereSet(somePath string) *PathSetIn {
 }
 
 func (s *NixCandidateSource) crawlKnownPaths() {
-	ForEachKnownPath(func(originalSource, expandedSource string) {
-		if s.expandedPathsAlreadyCrawled[expandedSource] {
-			return
+	ForEachKnownPath(s.crawlSource)
+}
+
+func (s *NixCandidateSource) crawlSource(originalSource, expandedSource string) {
+	if s.expandedPathsAlreadyCrawled[expandedSource] || isDir(expandedSource) {
+		return
+	}
+	// do not crawl this file again
+	s.expandedPathsAlreadyCrawled[expandedSource] = true
+
+	// try getting the contents
+	input, err := readAllText(expandedSource)
+	if err != nil {
+		return
+	}
+
+	ForEachVariableAssignment(s.key, input, func(value string) {
+		harvestedPaths := s.harvestPaths(value)
+		for _, harvestedPath := range harvestedPaths {
+			s.tryUpdatePathMap(harvestedPath, originalSource, expandedSource)
 		}
-		// do not crawl this file again
-		s.expandedPathsAlreadyCrawled[expandedSource] = true
+	})
+
+	sourcedQueue := []string{}
 
-		// try getting the contents
-		input, err := readAllText(expandedSource)
-		if err != nil {
+	ForEachSourcedScript(input, func(sourcedPath string) {
+		normalizedSourcedPath := s.fs.GetAbsolutePath(sourcedPath)
+		if s.expandedPathsAlreadyCrawled[normalizedSourcedPath] {
 			return
 		}
-
-		ForEachVariableAssignment(s.key, input, func(value string) {
-			harvestedPaths := s.harvestPaths(value)
-			for _, harvestedPath := range harvestedPaths {
-				s.tryUpdatePathMap(harvestedPath, originalSource, expandedSource)
-			}
-		})
+		sourcedQueue = append(sourcedQueue, sourcedPath)
 	})
+
+	for {
+		if len(sourcedQueue) == 0 {
+			break
+		}
+		next := sourcedQueue[0]
+		sourcedQueue = sourcedQueue[1:]
+		s.crawlSource(next, s.fs.GetAbsolutePath(next))
+	}
+
 }
 
 func (s *NixCandidateSource) tryUpdatePathMap(harvestedPath string, originalSource string, expandedSource string) {
@@ -93,14 +115,17 @@ func (s *NixCandidateSource) crawlPathLists() {
 
 // input is some path definition
 func (s *NixCandidateSource) harvestPaths(input string) []string {
+	input = fixHomeExpansion(input)
 	input = strings.TrimSpace(input)
 	input = strings.Trim(input, fmt.Sprintf("%v\"'", os.PathListSeparator))
 	inputExpanded := expand.Expand(input, func(key string) (value string, ok bool) {
+		switch key {
 		// do not expand the desired variable itself
-		if key == s.key {
+		case s.key:
 			return "", false
+		default:
+			return os.LookupEnv(key)
 		}
-		return os.LookupEnv(key)
 	})
 	all := strings.Split(inputExpanded, fmt.Sprintf("%c", os.PathListSeparator))
 	res := hashset.New[string](uint64(len(all)), g.Equals[string], g.HashString)
@@ -141,3 +166,11 @@ func appendIfNotInSlice[T any](input []T, value T, eq func(T, T) bool) []T {
 
 	return res
 }
+
+func isDir(p string) bool {
+	f, err := os.Stat(p)
+	if err != nil {
+		return false
+	}
+	return f.IsDir()
+}

common/os_filesystem.go

@@ -3,6 +3,7 @@ package common
 import (
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/mitchellh/go-homedir"
 	"go.spiff.io/expand"
@@ -12,6 +13,7 @@ type OsFilesystem struct{}
 
 func (*OsFilesystem) GetAbsolutePath(path string) string {
 	// homedir is assumed to work correctly
+	path = fixHomeExpansion(path)
 	expandedPath, err := homedir.Expand(path)
 	if err == nil {
 		path = expandedPath
@@ -23,6 +25,12 @@ func (*OsFilesystem) GetAbsolutePath(path string) string {
 	return expand.Expand(path, os.LookupEnv)
 }
 
+func fixHomeExpansion(path string) string {
+	path = strings.ReplaceAll(path, "$HOME/", "~/")
+	path = strings.ReplaceAll(path, "${HOME}/", "~/")
+	return path
+}
+
 // returns (exists, isDir)
 func (f *OsFilesystem) PathStatus(path string) (bool, bool) {
 	path = f.GetAbsolutePath(path)

common/os_filesystem_test.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"path"
 	"runtime"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -72,3 +73,11 @@ func createTempFile(t *testing.T) *os.File {
 	fmt.Println(tempFile.Name())
 	return tempFile
 }
+
+func Test_expanding_home_variable(t *testing.T) {
+	if os.Getenv("HOME") == "" {
+		os.Setenv("HOME", "/home")
+	}
+	expanded := sut.GetAbsolutePath("$HOME/.test/env")
+	assert.True(t, strings.HasSuffix(expanded, "/.test/env"))
+}

common/script_parser.go

@@ -15,7 +15,7 @@ func ForEachVariableAssignment(key, input string, fn func(string)) {
 	syntax.Walk(f, func(node syntax.Node) bool {
 		switch x := node.(type) {
 		case *syntax.Assign:
-			if key == x.Name.Value {
+			if x.Name != nil && key == x.Name.Value && x.Value != nil {
 				value := input[x.Value.Pos().Offset():x.Value.End().Offset()]
 				fn(value)
 			}
@@ -39,7 +39,7 @@ func ForEachSourcedScript(input string, fn func(string)) {
 	syntax.Walk(f, func(node syntax.Node) bool {
 		switch x := node.(type) {
 		case *syntax.CallExpr:
-			if len(x.Args) == 2 {
+			if len(x.Args) >= 2 {
 				cmd := input[x.Args[0].Pos().Offset():x.Args[0].End().Offset()]
 				cmd = strings.TrimLeft(cmd, "\\")