Fix ambiguity error in induced_subgraph (#54)

Author: mtfishman

Project.toml

@@ -1,7 +1,7 @@
 name = "DataGraphs"
 uuid = "b5a273c3-7e6c-41f6-98bd-8d7f1525a36a"
-version = "0.2.12"
 authors = ["Matthew Fishman <mfishman@flatironinstitute.org> and contributors"]
+version = "0.2.13"
 
 [deps]
 Dictionaries = "85a47980-9c8c-11e8-2b9f-f7ca1fa99fb4"
@@ -19,7 +19,7 @@ DataGraphsGraphsFlowsExt = "GraphsFlows"
 Dictionaries = "0.4"
 Graphs = "1"
 GraphsFlows = "0.1.1"
-NamedGraphs = "0.6.9, 0.7, 0.8"
+NamedGraphs = "0.8.2"
 SimpleTraits = "0.9"
 julia = "1.7"
 

src/abstractdatagraph.jl

@@ -40,6 +40,11 @@ edge_data_eltype(graph::AbstractDataGraph) = eltype(edge_data(graph))
 
 Base.zero(graph_type::Type{<:AbstractDataGraph}) = graph_type()
 
+# Graphs overloads
+function Graphs.vertices(graph::AbstractDataGraph)
+    return Graphs.vertices(underlying_graph(graph))
+end
+
 # Graphs overloads
 for f in [
         :(Graphs.a_star),
@@ -92,7 +97,6 @@ for f in [
         :(Graphs.steiner_tree),
         :(Graphs.topological_sort_by_dfs),
         :(Graphs.tree),
-        :(Graphs.vertices),
         :(GraphsExtensions.boundary_edges),
         :(GraphsExtensions.boundary_vertices),
         :(GraphsExtensions.eccentricities),
@@ -402,7 +406,7 @@ function Base.setindex!(graph::AbstractDataGraph, x, i1, i2, i...)
     return graph
 end
 
-function Graphs.induced_subgraph(graph::AbstractDataGraph, subvertices)
+function induced_subgraph_datagraph(graph::AbstractDataGraph, subvertices)
     underlying_subgraph, vlist = Graphs.induced_subgraph(underlying_graph(graph), subvertices)
     subgraph = similar_type(graph)(underlying_subgraph)
     for v in vertices(subgraph)
@@ -417,6 +421,15 @@ function Graphs.induced_subgraph(graph::AbstractDataGraph, subvertices)
     end
     return subgraph, vlist
 end
+function Graphs.induced_subgraph(graph::AbstractDataGraph, subvertices)
+    return induced_subgraph_datagraph(graph, subvertices)
+end
+# Fix ambiguity with Graphs.jl for integer `subvertices`.
+function Graphs.induced_subgraph(
+        graph::AbstractDataGraph, subvertices::AbstractVector{<:Integer}
+    )
+    return induced_subgraph_datagraph(graph, subvertices)
+end
 
 #
 # Printing

test/Project.toml

@@ -15,7 +15,7 @@ DataGraphs = "0.2.6"
 Dictionaries = "0.4.4"
 Graphs = "1.12"
 GraphsFlows = "0.1.1"
-NamedGraphs = "0.6.6, 0.7, 0.8"
+NamedGraphs = "0.8.2"
 SafeTestsets = "0.1"
 Suppressor = "0.2.8"
 Test = "1.10"

test/test_basics.jl

@@ -26,7 +26,7 @@ using Graphs:
 using Graphs.SimpleGraphs: SimpleDiGraph, SimpleEdge, SimpleGraph
 using GraphsFlows: GraphsFlows
 using NamedGraphs: NamedDiGraph, NamedEdge, NamedGraph
-using NamedGraphs.GraphsExtensions: ⊔, rename_vertices, vertextype
+using NamedGraphs.GraphsExtensions: ⊔, rename_vertices, subgraph, vertextype
 using NamedGraphs.NamedGraphGenerators: named_grid, named_path_graph
 using NamedGraphs.OrdinalIndexing: nd, st, rd, th
 using Test: @test, @test_broken, @testset
@@ -193,6 +193,40 @@ using Test: @test, @test_broken, @testset
         @test dg[1 => 2] == :default
     end
 
+    @testset "subgraph" begin
+        dg = DataGraph(named_path_graph(4))
+        dg[1] = "V1"
+        dg[2] = "V2"
+        dg[3] = "V3"
+        dg[4] = "V4"
+        dg[1 => 2] = "E12"
+        dg[2 => 3] = "E23"
+        dg[3 => 4] = "E34"
+        sg = subgraph(dg, [2, 3, 4])
+        @test nv(sg) == 3
+        @test ne(sg) == 2
+        @test !has_vertex(sg, 1)
+        @test has_vertex(sg, 2)
+        @test has_vertex(sg, 3)
+        @test has_vertex(sg, 4)
+        @test !has_edge(sg, 1 => 2)
+        @test !has_edge(sg, 2 => 1)
+        @test has_edge(sg, 2 => 3)
+        @test has_edge(sg, 3 => 2)
+        @test has_edge(sg, 3 => 4)
+        @test has_edge(sg, 4 => 3)
+        @test isnothing(get(sg, 1, nothing))
+        @test sg[2] == "V2"
+        @test sg[3] == "V3"
+        @test sg[4] == "V4"
+        @test isnothing(get(sg, 1 => 2, nothing))
+        @test isnothing(get(sg, 2 => 1, nothing))
+        @test sg[2 => 3] == "E23"
+        @test sg[3 => 2] == "E23"
+        @test sg[3 => 4] == "E34"
+        @test sg[4 => 3] == "E34"
+    end
+
     @testset "Constructors specifying vertex type" begin
         dg = DataGraph{Float64}(
             named_path_graph(4); vertex_data_eltype = String, edge_data_eltype = Symbol