chore: tests improvements

Author: denis256

…/changelog/v1.0.3/stack-dependencies.mdx …/changelog/v1.0.4/stack-dependencies.mdxdocs/src/data/changelog/v1.0.3/stack-dependencies.mdx renamed to docs/src/data/changelog/v1.0.4/stack-dependencies.mdx docs/src/data/changelog/v1.0.3/stack-dependencies.mdx renamed to docs/src/data/changelog/v1.0.4/stack-dependencies.mdx

@@ -1,5 +1,5 @@
 ---
-version: "v1.0.3"
+version: "v1.0.4"
 category: "experiments-updated"
 ---
 
@@ -36,21 +36,19 @@ unit "app" {
 }
 ```
 
-Nested stacks with `no_dot_terragrunt_stack = true` are also handled correctly, resolving to the stack's own directory rather than under `.terragrunt-stack/`.
-
 **Discovery commands surface stack dependencies**
 
 The `terragrunt find` and `terragrunt list` discovery commands now reflect stack dependencies generated by the `autoinclude` block. The DAG output correctly orders units by their autoinclude dependencies and shows dependency relationships in JSON, tree, and long formats.
 
 ```bash
 # JSON output includes dependency relationships from autoinclude
-terragrunt find --json --dag --dependencies --experiment stack-dependencies
+$ terragrunt find --json --dag --dependencies --experiment stack-dependencies
 
 # Long list format shows a Dependencies column
-terragrunt list --long --dependencies --dag --experiment stack-dependencies
+$ terragrunt list --long --dependencies --dag --experiment stack-dependencies
 
 # Tree format visualizes the dependency hierarchy
-terragrunt list --tree --dag --experiment stack-dependencies
+$ terragrunt list --tree --dag --experiment stack-dependencies
 ```
 
 Multi-level dependency trees (for example, `A → B,C` where `B → D,E`) are ordered correctly in DAG mode: leaf units appear first, parents appear after all their dependencies.

docs/src/data/experiments/stack-dependencies.mdx

@@ -143,3 +143,22 @@ Provide your feedback on the [Stack Dependencies RFC](https://github.com/gruntwo
 - [ ] Performance validation at scale
 
 </Since>
+
+<Since version="1.0.4">
+
+- [x] Create `internal/hclparse` package with two-phase stack file parser and autoinclude data structures
+- [x] Implement `terragrunt.autoinclude.hcl` file generator with relative path resolution
+- [x] Implement AST-walking partial evaluator for mixed `local.*` + `dependency.*` expressions
+- [x] Integrate autoinclude parsing and generation into `pkg/config/stack.go` stack generation pipeline
+- [x] Auto-merge `terragrunt.autoinclude.hcl` into unit config during `ParseConfig()` with deep merge
+- [x] Add `tryGetStackOutput()` for dependency blocks targeting stack directories
+- [x] Add `ExtractAutoIncludeDependencyPaths()` so DAG sees dependencies from autoinclude files
+- [x] Add integration tests and test fixtures for end-to-end validation
+- [x] E2E validation with `stack run apply` and `stack run destroy`
+- [x] Resolve `stack.<name>.<nested_stack>.path` at arbitrary nesting depth
+- [x] Surface autoinclude dependencies in `terragrunt find` and `terragrunt list` (JSON, tree, and long formats)
+- [ ] Community feedback on `autoinclude` syntax and merge behavior
+- [ ] Integration with CAS for generated files
+- [ ] Performance validation at scale
+
+</Since>

internal/hclparse/autoinclude.go

@@ -180,13 +180,15 @@ func BuildAutoIncludeEvalContext(unitRefs, stackRefs []ComponentRef) *hcl.EvalCo
 // AutoIncludeDependencyPaths reads the terragrunt.autoinclude.hcl file in
 // unitDir and returns resolved dependency config_path values.
 // Returns (nil, nil) if the file does not exist or has no dependencies.
+// Panics when fs is nil (programmer error). Returns EmptyArgError when unitDir
+// is empty so callers can distinguish bad input from a missing file.
 func AutoIncludeDependencyPaths(fs vfs.FS, unitDir string) ([]string, error) {
 	if fs == nil {
 		panic(fmt.Sprintf("hclparse.AutoIncludeDependencyPaths: fs is nil (unitDir=%q)", unitDir))
 	}
 
 	if unitDir == "" {
-		panic("hclparse.AutoIncludeDependencyPaths: unitDir is empty")
+		return nil, EmptyArgError{Func: "AutoIncludeDependencyPaths", Arg: "unitDir"}
 	}
 
 	unitDir = util.ResolvePath(unitDir)
@@ -197,7 +199,7 @@ func AutoIncludeDependencyPaths(fs vfs.FS, unitDir string) ([]string, error) {
 		return nil, err
 	}
 
-	var paths []string
+	paths := make([]string, 0, len(body.Blocks))
 
 	for _, block := range body.Blocks {
 		if depPath, ok := extractDependencyConfigPath(block, unitDir); ok {

internal/hclparse/errors.go

@@ -133,3 +133,13 @@ type LocalsMaxIterError struct {
 func (e LocalsMaxIterError) Error() string {
 	return fmt.Sprintf("locals evaluation exceeded %d iterations with %d unresolved locals", e.MaxIterations, e.Remaining)
 }
+
+// EmptyArgError indicates that a required string argument was empty.
+type EmptyArgError struct {
+	Func string
+	Arg  string
+}
+
+func (e EmptyArgError) Error() string {
+	return fmt.Sprintf("hclparse.%s: %s is empty", e.Func, e.Arg)
+}

internal/hclparse/fuzz_test.go

@@ -1,6 +1,7 @@
 package hclparse_test
 
 import (
+	"errors"
 	"testing"
 
 	"github.com/gruntwork-io/terragrunt/internal/hclparse"
@@ -372,10 +373,11 @@ func FuzzUnitPathsFromStackDir_ArgPanics(f *testing.F) {
 	})
 }
 
-// FuzzAutoIncludeDependencyPaths_ArgPanics fuzzes unitDir plus arbitrary file
+// FuzzAutoIncludeDependencyPaths_ArgErrors fuzzes unitDir plus arbitrary file
 // contents written to the in-memory FS, exercising both the argument-validation
-// panic and the HCL parsing path.
-func FuzzAutoIncludeDependencyPaths_ArgPanics(f *testing.F) {
+// error and the HCL parsing path. Empty unitDir must return EmptyArgError;
+// non-empty unitDir must not panic regardless of file content.
+func FuzzAutoIncludeDependencyPaths_ArgErrors(f *testing.F) {
 	f.Add("/unit", `dependency "vpc" { config_path = "../vpc" }`)
 	f.Add("", `dependency "x" {}`)
 	f.Add("/unit", ``)
@@ -392,17 +394,19 @@ func FuzzAutoIncludeDependencyPaths_ArgPanics(f *testing.F) {
 		}
 
 		defer func() {
-			r := recover()
-
-			switch {
-			case unitDir == "" && r == nil:
-				t.Errorf("expected panic for empty unitDir, got none")
-			case unitDir != "" && r != nil:
+			if r := recover(); r != nil {
 				t.Errorf("unexpected panic for unitDir=%q: %v", unitDir, r)
 			}
 		}()
 
-		_, _ = hclparse.AutoIncludeDependencyPaths(fs, unitDir)
+		_, err := hclparse.AutoIncludeDependencyPaths(fs, unitDir)
+
+		if unitDir == "" {
+			var emptyErr hclparse.EmptyArgError
+			if !errors.As(err, &emptyErr) {
+				t.Errorf("expected EmptyArgError for empty unitDir, got %v", err)
+			}
+		}
 	})
 }
 

internal/hclparse/panic_test.go

@@ -103,11 +103,16 @@ func TestAutoIncludeDependencyPaths_NilFS_Panics(t *testing.T) {
 	})
 }
 
-func TestAutoIncludeDependencyPaths_EmptyUnitDir_Panics(t *testing.T) {
+func TestAutoIncludeDependencyPaths_EmptyUnitDir_ReturnsError(t *testing.T) {
 	t.Parallel()
-	assertPanicsContaining(t, "hclparse.AutoIncludeDependencyPaths: unitDir is empty", func() {
-		_, _ = hclparse.AutoIncludeDependencyPaths(vfs.NewMemMapFS(), "")
-	})
+
+	paths, err := hclparse.AutoIncludeDependencyPaths(vfs.NewMemMapFS(), "")
+	require.Nil(t, paths)
+
+	var emptyErr hclparse.EmptyArgError
+	require.ErrorAs(t, err, &emptyErr)
+	assert.Equal(t, "AutoIncludeDependencyPaths", emptyErr.Func)
+	assert.Equal(t, "unitDir", emptyErr.Arg)
 }
 
 func TestGenerateAutoIncludeFile_NilFS_Panics(t *testing.T) {