From 24b91f79d0c20375651af6a9106188cae7073882 Mon Sep 17 00:00:00 2001
From: Radek Simko <radek.simko@gmail.com>
Date: Wed, 18 Nov 2020 16:00:46 +0000
Subject: [PATCH] Avoid panic by initing universal schema early (#307)

---
 internal/terraform/rootmodule/root_module.go  | 29 +++++--------------
 .../rootmodule/root_module_manager.go         |  9 ------
 internal/terraform/rootmodule/types.go        |  1 -
 3 files changed, 8 insertions(+), 31 deletions(-)

diff --git a/internal/terraform/rootmodule/root_module.go b/internal/terraform/rootmodule/root_module.go
index c66f3144f..f43a1b063 100644
--- a/internal/terraform/rootmodule/root_module.go
+++ b/internal/terraform/rootmodule/root_module.go
@@ -64,9 +64,8 @@ type rootModule struct {
 	tfVersionErr error
 
 	// core schema
-	coreSchemaLoaded bool
-	coreSchema       *schema.BodySchema
-	coreSchemaMu     *sync.RWMutex
+	coreSchema   *schema.BodySchema
+	coreSchemaMu *sync.RWMutex
 
 	// decoder
 	isParsed    bool
@@ -88,6 +87,7 @@ func newRootModule(fs filesystem.Filesystem, dir string) *rootModule {
 		pluginMu:         &sync.RWMutex{},
 		providerSchemaMu: &sync.RWMutex{},
 		tfLoadingMu:      &sync.RWMutex{},
+		coreSchema:       tfschema.UniversalCoreModuleSchema(),
 		coreSchemaMu:     &sync.RWMutex{},
 		isParsedMu:       &sync.RWMutex{},
 		pFilesMap:        make(map[string]*hcl.File, 0),
@@ -327,8 +327,9 @@ func (rm *rootModule) findAndSetCoreSchema() error {
 		return err
 	}
 
+	rm.coreSchemaMu.Lock()
 	rm.coreSchema = coreSchema
-	rm.setCoreSchemaLoaded(true)
+	rm.coreSchemaMu.Unlock()
 
 	return nil
 }
@@ -398,18 +399,6 @@ func (rm *rootModule) Decoder() (*decoder.Decoder, error) {
 	return d, nil
 }
 
-func (rm *rootModule) IsCoreSchemaLoaded() bool {
-	rm.coreSchemaMu.RLock()
-	defer rm.coreSchemaMu.RUnlock()
-	return rm.coreSchemaLoaded
-}
-
-func (rm *rootModule) setCoreSchemaLoaded(isLoaded bool) {
-	rm.coreSchemaMu.Lock()
-	defer rm.coreSchemaMu.Unlock()
-	rm.coreSchemaLoaded = isLoaded
-}
-
 func (rm *rootModule) IsProviderSchemaLoaded() bool {
 	rm.providerSchemaMu.RLock()
 	defer rm.providerSchemaMu.RUnlock()
@@ -489,11 +478,9 @@ func (rm *rootModule) parsedFiles() map[string]*hcl.File {
 }
 
 func (rm *rootModule) MergedSchema() (*schema.BodySchema, error) {
-	var mergedSchema *schema.BodySchema
-
-	if rm.IsCoreSchemaLoaded() {
-		mergedSchema = rm.coreSchema
-	}
+	rm.coreSchemaMu.RLock()
+	defer rm.coreSchemaMu.RUnlock()
+	mergedSchema := rm.coreSchema
 
 	if rm.IsProviderSchemaLoaded() {
 		if !rm.IsParsed() {
diff --git a/internal/terraform/rootmodule/root_module_manager.go b/internal/terraform/rootmodule/root_module_manager.go
index 7f6ea68f2..63e64615c 100644
--- a/internal/terraform/rootmodule/root_module_manager.go
+++ b/internal/terraform/rootmodule/root_module_manager.go
@@ -219,15 +219,6 @@ func (rmm *rootModuleManager) RootModuleByPath(path string) (RootModule, error)
 	return nil, &RootModuleNotFoundErr{path}
 }
 
-func (rmm *rootModuleManager) IsCoreSchemaLoaded(path string) (bool, error) {
-	rm, err := rmm.RootModuleByPath(path)
-	if err != nil {
-		return false, err
-	}
-
-	return rm.IsCoreSchemaLoaded(), nil
-}
-
 func (rmm *rootModuleManager) IsProviderSchemaLoaded(path string) (bool, error) {
 	rm, err := rmm.RootModuleByPath(path)
 	if err != nil {
diff --git a/internal/terraform/rootmodule/types.go b/internal/terraform/rootmodule/types.go
index fb7bc4b33..14b70f19a 100644
--- a/internal/terraform/rootmodule/types.go
+++ b/internal/terraform/rootmodule/types.go
@@ -77,7 +77,6 @@ type RootModule interface {
 	IsParsed() bool
 	ParseFiles() error
 	ParsedDiagnostics() map[string]hcl.Diagnostics
-	IsCoreSchemaLoaded() bool
 	TerraformFormatter() (exec.Formatter, error)
 	HasTerraformDiscoveryFinished() bool
 	IsTerraformAvailable() bool