Method RenameVariablePrefix

hclwrite/ast_expression.go:153–188

RenameVariablePrefix examines each of the absolute traversals in the receiving expression to see if they have the given sequence of names as a prefix prefix. If so, they are updated in place to have the given replacement names instead of that prefix. This can be used to implement symbol renaming. T

(search, replacement []string)

// method will panic. Only attribute access operations can be matched and
// replaced. Index steps never match the prefix.
func (e *Expression) RenameVariablePrefix(search, replacement []string) {
	if len(search) != len(replacement) {
		panic(fmt.Sprintf("search and replacement length mismatch (%d and %d)", len(search), len(replacement)))
	}
Traversals:
	for node := range e.absTraversals {
		traversal := node.content.(*Traversal)
		if len(traversal.steps) < len(search) {
			// If it's shorter then it can't have our prefix
			continue
		}

		stepNodes := traversal.steps.List()
		for i, name := range search {
			step, isName := stepNodes[i].content.(*TraverseName)
			if !isName {
				continue Traversals // only name nodes can match
			}
			foundNameBytes := step.name.content.(*identifier).token.Bytes
			if len(foundNameBytes) != len(name) {
				continue Traversals
			}
			if string(foundNameBytes) != name {
				continue Traversals
			}
		}

		// If we get here then the prefix matched, so now we'll swap in
		// the replacement strings.
		for i, name := range replacement {
			step := stepNodes[i].content.(*TraverseName)
			token := step.name.content.(*identifier).token
			token.Bytes = []byte(name)
		}
	}
}

// Traversal represents a sequence of variable, attribute, and/or index
// operations.