Generalize core changes checking routine

Wipe the workspace if any of the core files has changed; this solves a long-standing
problem for core developers about changes in platform.txt requiring a manual wipe to be correctly applied

Author: facchinm

src/arduino.cc/builder/builder_utils/utils.go

@@ -287,22 +287,26 @@ func nonEmptyString(s string) bool {
 	return s != constants.EMPTY_STRING
 }
 
-func CheckIfRecompileIsAvoidable(corePath string, archiveFile string) bool {
-	archiveFileStat, err := os.Stat(archiveFile)
+func CoreOrReferencedCoreHasChanged(corePath, targetCorePath, targetFile string) bool {
+
+	targetFileStat, err := os.Stat(targetFile)
 	if err == nil {
 		files, err := findAllFilesInFolder(corePath, true)
 		if err != nil {
-			return false
+			return true
 		}
 		for _, file := range files {
 			fileStat, err := os.Stat(file)
-			if err != nil || fileStat.ModTime().After(archiveFileStat.ModTime()) {
-				return false
+			if err != nil || fileStat.ModTime().After(targetFileStat.ModTime()) {
+				return true
 			}
 		}
-		return true
+		if targetCorePath != constants.EMPTY_STRING && !strings.EqualFold(corePath, targetCorePath) {
+			return CoreOrReferencedCoreHasChanged(targetCorePath, constants.EMPTY_STRING, targetFile)
+		}
+		return false
 	}
-	return false
+	return true
 }
 
 func ArchiveCompiledFiles(buildPath string, archiveFile string, objectFiles []string, buildProperties properties.Map, verbose bool, logger i18n.Logger) (string, error) {

src/arduino.cc/builder/phases/core_builder.go

@@ -36,7 +36,6 @@ import (
 	"arduino.cc/builder/types"
 	"arduino.cc/builder/utils"
 	"arduino.cc/properties"
-	"strings"
 )
 
 type CoreBuilder struct{}
@@ -91,14 +90,9 @@ func compileCore(buildPath string, buildProperties properties.Map, verbose bool,
 	realCoreFolder := utils.GetParentFolder(coreFolder, 2)
 
 	targetArchivedCore := builder_utils.GetCoreArchivePath(buildProperties[constants.BUILD_PROPERTIES_FQBN])
-	noNeedToRecompile := builder_utils.CheckIfRecompileIsAvoidable(realCoreFolder, targetArchivedCore)
+	canUseArchivedCore := !builder_utils.CoreOrReferencedCoreHasChanged(realCoreFolder, targetCoreFolder, targetArchivedCore)
 
-	if !strings.EqualFold(realCoreFolder, targetCoreFolder) {
-		// targetCoreFolder is not a parent of realCoreFolder, so check it for modifications
-		noNeedToRecompile = noNeedToRecompile && builder_utils.CheckIfRecompileIsAvoidable(targetCoreFolder, targetArchivedCore)
-	}
-
-	if noNeedToRecompile {
+	if canUseArchivedCore {
 		// use archived core
 		if verbose {
 			logger.Println(constants.LOG_LEVEL_INFO, "Using precompiled core")

src/arduino.cc/builder/wipeout_build_path_if_build_options_changed.go

@@ -34,10 +34,12 @@ import (
 	"os"
 	"path/filepath"
 
+	"arduino.cc/builder/builder_utils"
 	"arduino.cc/builder/constants"
 	"arduino.cc/builder/gohasissues"
 	"arduino.cc/builder/i18n"
 	"arduino.cc/builder/types"
+	"arduino.cc/builder/utils"
 	"arduino.cc/properties"
 )
 
@@ -62,7 +64,17 @@ func (s *WipeoutBuildPathIfBuildOptionsChanged) Run(ctx *types.Context) error {
 		delete(prevOpts, "sketchLocation")
 	}
 
-	if opts.Equals(prevOpts) {
+	// check if any of the files contained in the core folders has changed
+	// since the json was generated - like platform.txt or similar
+	// if so, trigger a "safety" wipe
+	buildProperties := ctx.BuildProperties
+	targetCoreFolder := buildProperties[constants.BUILD_PROPERTIES_RUNTIME_PLATFORM_PATH]
+	coreFolder := buildProperties[constants.BUILD_PROPERTIES_BUILD_CORE_PATH]
+	realCoreFolder := utils.GetParentFolder(coreFolder, 2)
+	jsonPath := filepath.Join(ctx.BuildPath, constants.BUILD_OPTIONS_FILE)
+	coreHasChanged := builder_utils.CoreOrReferencedCoreHasChanged(realCoreFolder, targetCoreFolder, jsonPath)
+
+	if opts.Equals(prevOpts) && !coreHasChanged {
 		return nil
 	}