refactor: Replace _impl aliases with explicit wrapper functions in R/topology.R

[Copilot]

Replace _impl aliases in R/topology.R with explicit wrapper functions

Summary:
Successfully replaced all direct _impl function aliases with explicit wrapper functions that properly preserve the missing state of optional parameters.

Changes completed:

• Applied if (missing(arg)) missing_arg() else arg pattern to all color-related parameters
• Updated graph.isomorphic.bliss - colors1, colors2
• Updated graph.isomorphic.vf2 - vertex.color1, vertex.color2, edge.color1, edge.color2
• Updated graph.subisomorphic.vf2 - vertex.color1, vertex.color2, edge.color1, edge.color2
• Updated graph.count.isomorphisms.vf2 - vertex.color1, vertex.color2, edge.color1, edge.color2
• Updated graph.count.subisomorphisms.vf2 - vertex.color1, vertex.color2, edge.color1, edge.color2
• Updated canonical_permutation - colors
• Updated count_automorphisms - colors (already done in previous commit)
• Updated automorphism_group - colors
• All tests passing (6952 pass, 0 fail)

Pattern applied:
The pattern uses rlang::missing_arg() to preserve the missing state of optional parameters. When a wrapper function receives an optional parameter that wasn't provided by the caller, it forwards a missing argument marker to the _impl function, allowing the _impl function's is_missing() check to work correctly.

Example:

canonical_permutation <- function(graph, colors = NULL, sh = c("fm", "f", "fs", "fl", "flm", "fsm")) {
  canonical_permutation_impl(
    graph = graph,
    colors = if (missing(colors)) missing_arg() else colors,
    sh = sh
  )
}

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Replace _impl aliases in R/topology.R</issue_title>
<issue_description>Goal
Review the code in R/topology.R and replace all direct _impl function aliases with explicit wrapper functions.

Functions to update:

• graph.isomorphic.bliss <- isomorphic_bliss_impl
• graph.isomorphic.vf2 <- isomorphic_vf2_impl
• graph.subisomorphic.vf2 <- subisomorphic_vf2_impl
• graph.count.isomorphisms.vf2 <- count_isomorphisms_vf2_impl
• graph.count.subisomorphisms.vf2 <- count_subisomorphisms_vf2_impl
• graph.isoclass <- isoclass_impl
• graph_from_isomorphism_class <- isoclass_create_impl
• canonical_permutation <- canonical_permutation_bliss_impl
• permute <- permute_vertices_impl
• graph.isomorphic <- isomorphic_impl
• count_automorphisms <- count_automorphisms_bliss_impl
• automorphism_group <- automorphism_group_impl

Instructions

1. Review the code to understand the function signatures
2. Create explicit wrapper functions that forward to the _impl functions
3. Forward each argument individually and explicitly using arg = arg notation
4. Do not use ... unless the _impl function itself uses ...

Pattern
Replace direct aliasing like:

func_name <- func_name_impl

With an explicit wrapper:

func_name <- function(arg1, arg2, ...) {
  func_name_impl(
    arg1 = arg1,
    arg2 = arg2,
    ...
  )
}

File
R/topology.R</issue_description>

<agent_instructions>A few functions have been replaced already. IMPORTANT: For this issue, failing tests are acceptable. Implement a simple forwarding and come back with the result, even if the tests fail.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Replace _impl aliases in R/topology.R #2366

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[krlmlr]

@copilot: Apply the pattern from the last commit across all relevant arguments. IMPORTANT: Do not use other patterns. Test and report if successful.

[Copilot]

@copilot: Apply the pattern from the last commit across all relevant arguments. IMPORTANT: Do not use other patterns. Test and report if successful.

Applied the if (missing(arg)) missing_arg() else arg pattern to all color-related parameters in the wrapper functions. All tests now pass (6952 pass, 0 fail). Fixed in commit e9ba27c.