Moved ResolveLibrary function in the correct source file

Author: cmaglie

legacy/builder/container_find_includes.go

@@ -455,3 +455,48 @@ func queueSourceFilesFromFolder(ctx *types.Context, sourceFileQueue *types.Uniqu
 
 	return nil
 }
+
+func ResolveLibrary(ctx *types.Context, header string) *libraries.Library {
+	resolver := ctx.LibrariesResolver
+	importedLibraries := ctx.ImportedLibraries
+
+	candidates := resolver.AlternativesFor(header)
+
+	if ctx.Verbose {
+		ctx.Info(tr("Alternatives for %[1]s: %[2]s", header, candidates))
+		ctx.Info(fmt.Sprintf("ResolveLibrary(%s)", header))
+		ctx.Info(fmt.Sprintf("  -> %s: %s", tr("candidates"), candidates))
+	}
+
+	if len(candidates) == 0 {
+		return nil
+	}
+
+	for _, candidate := range candidates {
+		if importedLibraries.Contains(candidate) {
+			return nil
+		}
+	}
+
+	selected := resolver.ResolveFor(header, ctx.TargetPlatform.Platform.Architecture)
+	if alreadyImported := importedLibraries.FindByName(selected.Name); alreadyImported != nil {
+		// Certain libraries might have the same name but be different.
+		// This usually happens when the user includes two or more custom libraries that have
+		// different header name but are stored in a parent folder with identical name, like
+		// ./libraries1/Lib/lib1.h and ./libraries2/Lib/lib2.h
+		// Without this check the library resolution would be stuck in a loop.
+		// This behaviour has been reported in this issue:
+		// https://github.com/arduino/arduino-cli/issues/973
+		if selected == alreadyImported {
+			selected = alreadyImported
+		}
+	}
+
+	candidates.Remove(selected)
+	ctx.LibrariesResolutionResults[header] = types.LibraryResolutionResult{
+		Library:          selected,
+		NotUsedLibraries: candidates,
+	}
+
+	return selected
+}