Update helpers with a pathutils sub-package to help with the new path.Expressions manipulation

Author: Ivan De Marino

helpers/pathutils/merge.go

@@ -0,0 +1,30 @@
+package pathutils
+
+import (
+	"github.com/hashicorp/terraform-plugin-framework/path"
+)
+
+// MergeExpressionsWithAttribute returns the given path.Expressions,
+// but each has been merged with the given attribute path.Expression,
+// and then resolved.
+//
+// Additionally, if the attribute path.Expression was not part of the initial slice,
+// it is added to the result.
+func MergeExpressionsWithAttribute(pathExps path.Expressions, attrPathExp path.Expression) path.Expressions {
+	result := make(path.Expressions, 0, len(pathExps)+1)
+
+	// First, add the attribute own path expression to the result
+	result = append(result, attrPathExp)
+
+	for _, pe := range pathExps {
+		mpe := attrPathExp.Merge(pe).Resolve()
+
+		// Include the merged path expression,
+		// only if it's not the same as the attribute
+		if !mpe.Equal(attrPathExp) {
+			result = append(result, mpe)
+		}
+	}
+
+	return result
+}

helpers/pathutils/resolve.go

@@ -0,0 +1,47 @@
+package pathutils
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/hashicorp/terraform-plugin-framework-validators/helpers/validatordiag"
+	"github.com/hashicorp/terraform-plugin-framework/diag"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/tfsdk"
+)
+
+// PathMatchExpressionsAgainstAttributeConfig returns the path.Paths matching the given path.Expressions.
+//
+// Each path.Expression has been merged with the given attribute path.Expression
+// (likely from the tfsdk.ValidateAttributeRequest), resolved,
+// and then matched against the given attribute tfsdk.Config (also from the tfsdk.ValidateAttributeRequest).
+//
+// This is useful for tfsdk.AttributeValidator that accept path.Expressions, and validate the attributes matching
+// to the expressions, in relation to the attribute the validator is applied to.
+// For example usage, please look at the `schemavalidator` package in this repository.
+func PathMatchExpressionsAgainstAttributeConfig(ctx context.Context, pathExps path.Expressions, attrPathExp path.Expression, attrConfig tfsdk.Config) (path.Paths, diag.Diagnostics) {
+	var resDiags diag.Diagnostics
+
+	pathExpressions := MergeExpressionsWithAttribute(pathExps, attrPathExp)
+
+	resPaths := make(path.Paths, 0, len(pathExpressions))
+
+	for _, pe := range pathExpressions {
+		// Retrieve all the attribute paths that match the given expressions
+		matchingPaths, diags := attrConfig.PathMatches(ctx, pe)
+		resDiags.Append(diags...)
+		if diags.HasError() {
+			return nil, resDiags
+		}
+
+		// Confirm at least one attribute was matched.
+		// If not, collect errors so that the callee can bubble the bugs up.
+		if len(matchingPaths) == 0 {
+			resDiags.Append(validatordiag.BugInProviderDiagnostic(fmt.Sprintf("Path expression %q matches no attribute", pe)))
+		}
+
+		resPaths = append(resPaths, matchingPaths...)
+	}
+
+	return resPaths, resDiags
+}

helpers/validatordiag/diag.go

@@ -35,8 +35,8 @@ func InvalidAttributeValueMatchDiagnostic(path path.Path, description string, va
 	)
 }
 
-// InvalidAttributeSchemaDiagnostic returns an error Diagnostic to be used when a schemavalidator of attributes is invalid.
-func InvalidAttributeSchemaDiagnostic(path path.Path, description string) diag.Diagnostic {
+// InvalidAttributeCombinationDiagnostic returns an error Diagnostic to be used when a schemavalidator of attributes is invalid.
+func InvalidAttributeCombinationDiagnostic(path path.Path, description string) diag.Diagnostic {
 	return diag.NewAttributeErrorDiagnostic(
 		path,
 		"Invalid Attribute Combination",
@@ -53,30 +53,10 @@ func InvalidAttributeTypeDiagnostic(path path.Path, description string, value st
 	)
 }
 
-// ErrorsCount returns the amount of diag.Diagnostic in diag.Diagnostics that are diag.SeverityError.
-func ErrorsCount(diags diag.Diagnostics) int {
-	count := 0
-
-	for _, d := range diags {
-		if diag.SeverityError == d.Severity() {
-			count++
-		}
-	}
-
-	return count
-}
-
-// WarningsCount returns the amount of diag.Diagnostic in diag.Diagnostics that are diag.SeverityWarning.
-func WarningsCount(diags diag.Diagnostics) int {
-	count := 0
-
-	for _, d := range diags {
-		if diag.SeverityWarning == d.Severity() {
-			count++
-		}
-	}
-
-	return count
+func BugInProviderDiagnostic(summary string) diag.Diagnostic {
+	return diag.NewErrorDiagnostic(summary,
+		"This is a bug in the provider, which should be reported in the provider's own issue tracker",
+	)
 }
 
 // capitalize will uppercase the first letter in a UTF-8 string.