librariesindex: Fix nil pointer. Refs #1176

Let the library index return the latest known version,
if a library without a version is found.

Signed-off-by: Ruben Jenster <[email protected]>

Author: r10r

arduino/libraries/librariesindex/index.go

@@ -16,6 +16,7 @@
 package librariesindex
 
 import (
+	"fmt"
 	"sort"
 
 	"github.com/arduino/arduino-cli/arduino/libraries"
@@ -136,6 +137,10 @@ func (idx *Index) FindLibraryUpdate(lib *libraries.Library) *Release {
 	if indexLib == nil {
 		return nil
 	}
+	if lib.Version == nil {
+		fmt.Printf("[WARN] version for library loaded from %s is nil\n", lib.InstallDir)
+		return indexLib.Latest
+	}
 	if indexLib.Latest.Version.GreaterThan(lib.Version) {
 		return indexLib.Latest
 	}

arduino/libraries/librariesindex/index_test.go

@@ -78,6 +78,10 @@ func TestIndexer(t *testing.T) {
 	require.NotNil(t, rtcUpdate)
 	require.Equal(t, "RTCZero@1.6.0", rtcUpdate.String())
 
+	rtcUpdateNoVersion := index.FindLibraryUpdate(&libraries.Library{Name: "RTCZero", Version: nil})
+	require.NotNil(t, rtcUpdateNoVersion)
+	require.Equal(t, "RTCZero@1.6.0", rtcUpdateNoVersion.String())
+
 	rtcNoUpdate := index.FindLibraryUpdate(&libraries.Library{Name: "RTCZero", Version: semver.MustParse("3.0.0")})
 	require.Nil(t, rtcNoUpdate)