Fixed nil pointer exception in build options extraction

Author: cmaglie

Diff for: legacy/builder/libraries_loader.go

@@ -36,10 +36,12 @@ func (s *LibrariesLoader) Run(ctx *types.Context) error {
 		ctx.LibrariesManager = lm
 
 		builtInLibrariesFolders := ctx.BuiltInLibrariesDirs
-		if err := builtInLibrariesFolders.ToAbs(); err != nil {
-			return errors.WithStack(err)
+		if builtInLibrariesFolders != nil {
+			if err := builtInLibrariesFolders.ToAbs(); err != nil {
+				return errors.WithStack(err)
+			}
+			lm.AddLibrariesDir(builtInLibrariesFolders, libraries.IDEBuiltIn)
 		}
-		lm.AddLibrariesDir(builtInLibrariesFolders, libraries.IDEBuiltIn)
 
 		if ctx.ActualPlatform != ctx.TargetPlatform {
 			lm.AddPlatformReleaseLibrariesDir(ctx.ActualPlatform, libraries.ReferencedPlatformBuiltIn)

Diff for: legacy/builder/test/create_build_options_map_test.go

@@ -43,7 +43,6 @@ func TestCreateBuildOptionsMap(t *testing.T) {
 
 	require.Equal(t, `{
   "additionalFiles": "",
-  "builtInLibrariesFolders": "",
   "builtInToolsFolders": "tools",
   "compiler.optimization_flags": "-Os",
   "customBuildProperties": "",

Diff for: legacy/builder/types/context.go

@@ -208,7 +208,9 @@ func (ctx *Context) ExtractBuildOptions() *properties.Map {
 	opts := properties.NewMap()
 	opts.Set("hardwareFolders", strings.Join(ctx.HardwareDirs.AsStrings(), ","))
 	opts.Set("builtInToolsFolders", strings.Join(ctx.BuiltInToolsDirs.AsStrings(), ","))
-	opts.Set("builtInLibrariesFolders", ctx.BuiltInLibrariesDirs.String())
+	if ctx.BuiltInLibrariesDirs != nil {
+		opts.Set("builtInLibrariesFolders", ctx.BuiltInLibrariesDirs.String())
+	}
 	opts.Set("otherLibrariesFolders", strings.Join(ctx.OtherLibrariesDirs.AsStrings(), ","))
 	opts.SetPath("sketchLocation", ctx.SketchLocation)
 	var additionalFilesRelative []string

Diff for: legacy/builder/types/context_test.go

@@ -0,0 +1,61 @@
+// This file is part of arduino-cli.
+//
+// Copyright 2022 ARDUINO SA (http://www.arduino.cc/)
+//
+// This software is released under the GNU General Public License version 3,
+// which covers the main part of arduino-cli.
+// The terms of this license can be found at:
+// https://www.gnu.org/licenses/gpl-3.0.en.html
+//
+// You can be released from the requirements of the above licenses by purchasing
+// a commercial license. Buying such a license is mandatory if you want to
+// modify or otherwise use the software for commercial activities involving the
+// Arduino software without disclosing the source code of your own applications.
+// To purchase a commercial license, send an email to [email protected].
+
+package types
+
+import (
+	"testing"
+
+	"github.com/arduino/arduino-cli/arduino/cores"
+	paths "github.com/arduino/go-paths-helper"
+	"github.com/stretchr/testify/require"
+)
+
+func TestInjectBuildOption(t *testing.T) {
+	fqbn, err := cores.ParseFQBN("aaa:bbb:ccc")
+	require.NoError(t, err)
+
+	{
+		ctx := &Context{
+			HardwareDirs:          paths.NewPathList("aaa", "bbb"),
+			BuiltInToolsDirs:      paths.NewPathList("ccc", "ddd"),
+			BuiltInLibrariesDirs:  paths.New("eee"),
+			OtherLibrariesDirs:    paths.NewPathList("fff", "ggg"),
+			SketchLocation:        paths.New("hhh"),
+			FQBN:                  fqbn,
+			ArduinoAPIVersion:     "iii",
+			CustomBuildProperties: []string{"jjj", "kkk"},
+			OptimizationFlags:     "lll",
+		}
+		newCtx := &Context{}
+		newCtx.InjectBuildOptions(ctx.ExtractBuildOptions())
+		require.Equal(t, ctx, newCtx)
+	}
+	{
+		ctx := &Context{
+			HardwareDirs:          paths.NewPathList("aaa", "bbb"),
+			BuiltInToolsDirs:      paths.NewPathList("ccc", "ddd"),
+			OtherLibrariesDirs:    paths.NewPathList("fff", "ggg"),
+			SketchLocation:        paths.New("hhh"),
+			FQBN:                  fqbn,
+			ArduinoAPIVersion:     "iii",
+			CustomBuildProperties: []string{"jjj", "kkk"},
+			OptimizationFlags:     "lll",
+		}
+		newCtx := &Context{}
+		newCtx.InjectBuildOptions(ctx.ExtractBuildOptions())
+		require.Equal(t, ctx, newCtx)
+	}
+}