Allow empty username when it's not used

docs/src/developer.md

@@ -297,12 +297,13 @@ For more examples, see the plugins in the [Continuous Integration (CI)](@ref) an
 
 For an overview of writing template files for Mustache.jl, see [Custom Template Files](@ref) in the user guide.
 
-### Traits
+### Predicates
 
-There are a few traits for plugin types that are occassionally used to answer questions like "does this `Template` have any code coverage plugins?".
+There are a few predicate functions for plugins that are occasionally used to answer questions like "does this `Template` have any code coverage plugins?".
-If you're implementing a plugin that fits into one of the following categories, it would be wise to implement the corresponding trait function to return `true` for your type.
+If you're implementing a plugin that fits into one of the following categories, it would be wise to implement the corresponding predicate function to return `true` for instances of your type.
 
 ```@docs
+needs_username
 is_ci
 is_coverage
 ```

src/plugin.jl

@@ -218,6 +218,14 @@ function render_text(text::AbstractString, view::Dict{<:AbstractString}, tags=no
     return tags === nothing ? render(text, view) : render(text, view; tags=tags)
 end
 
+"""
+    needs_username(::Plugin) -> Bool
+
+Determine whether or not a plugin needs a Git hosting service username to function correctly.
+If you are implementing a plugin that uses the `user` field of a [`Template`](@ref), you should implement this function and return `true`.
+"""
+needs_username(::Plugin) = false
+
 include(joinpath("plugins", "project_file.jl"))
 include(joinpath("plugins", "src_dir.jl"))
 include(joinpath("plugins", "tests.jl"))

src/plugins/ci.jl

@@ -261,3 +261,5 @@ If you are adding a CI plugin, you should implement this function and return `tr
 """
 is_ci(::Plugin) = false
 is_ci(::Union{AppVeyor, TravisCI, CirrusCI, GitLabCI}) = true
+
+needs_username(::Union{AppVeyor, TravisCI, CirrusCI, GitLabCI}) = true

src/plugins/citation.jl

@@ -24,3 +24,5 @@ view(::Citation, t::Template, pkg::AbstractString) = Dict(
     "URL" => "https://$(t.host)/$(t.user)/$pkg.jl",
     "YEAR" => year(today()),
 )
+
+needs_username(::Citation) = true

src/plugins/coverage.jl

@@ -52,3 +52,5 @@ If you are adding a coverage plugin, you should implement this function and retu
 """
 is_coverage(::Plugin) = false
 is_coverage(::Union{Codecov, Coveralls}) = true
+
+needs_username(::Union{Codecov, Coveralls}) = true

src/plugins/documenter.jl

@@ -110,3 +110,5 @@ gitlab_pages_url(t::Template, pkg::AbstractString) = "https://$(t.user).gitlab.i
 make_canonical(::Type{TravisCI}) = github_pages_url
 make_canonical(::Type{GitLabCI}) = gitlab_pages_url
 make_canonical(::Type{Nothing}) = nothing
+
+needs_username(::Documenter) = true

src/plugins/git.jl

@@ -88,3 +88,5 @@ function commit(p::Git, repo::GitRepo, pkg_dir::AbstractString, msg::AbstractStr
         LibGit2.commit(repo, msg)
     end
 end
+
+needs_username(::Git) = true

src/template.jl

@@ -19,7 +19,7 @@ A configuration used to generate packages.
 ### User Options
 - `user::AbstractString="$(default_user())"`: GitHub (or other code hosting service) username.
   The default value comes from the global Git config (`github.user`).
-  If no value is obtained, an `ArgumentError` is thrown.
+  If no value is obtained, many plugins that use this value will not work.
 - `authors::Union{AbstractString, Vector{<:AbstractString}}="$(default_authors())"`: Package authors.
   Like `user`, it takes its default value from the global Git config (`user.name` and `user.email`).
 
@@ -61,15 +61,13 @@ Template(; interactive::Bool=false, kwargs...) = Template(Val(interactive); kwar
 # Non-interactive constructor.
 function Template(::Val{false}; kwargs...)
     user = getkw(kwargs, :user)
-    isempty(user) && throw(ArgumentError("No user set, please pass user=username"))
-
-    authors = getkw(kwargs, :authors)
-    authors isa Vector || (authors = map(strip, split(authors, ",")))
-
     dir = abspath(expanduser(getkw(kwargs, :dir)))
     host = replace(getkw(kwargs, :host), r".*://" => "")
     julia_version = getkw(kwargs, :julia_version)
 
+    authors = getkw(kwargs, :authors)
+    authors isa Vector || (authors = map(strip, split(authors, ",")))
+
     # User-supplied plugins come first, so that deduping the list will remove the defaults.
     plugins = Plugin[]
     append!(plugins, getkw(kwargs, :plugins))
@@ -77,6 +75,16 @@ function Template(::Val{false}; kwargs...)
     append!(plugins, filter(p -> !(typeof(p) in disabled), default_plugins()))
     plugins = sort(unique(typeof, plugins); by=string)
 
+    if isempty(user)
+        foreach(plugins) do p
+            if needs_username(p)
+                T = nameof(typeof(p))
+                s = "$T: Git hosting service username is required, supply user=username"
+                throw(ArgumentError(s))
+            end
+        end
+    end
+
     return Template(authors, dir, host, julia_version, plugins, user)
 end
 

test/template.jl

@@ -1,12 +1,14 @@
 @testset "Template" begin
     @testset "Template constructor" begin
         @testset "user" begin
-            if isempty(PT.default_user())
+            mock(PT.default_user => () -> "") do _du
                 @test_throws ArgumentError Template()
-                haskey(ENV, "CI") && run(`git config --global github.user $USER`)
+                @test isempty(Template(; disable_defaults=[Git]).user)
             end
+            mock(PT.default_user => () -> "username") do _du
                 @test Template().user == PT.default_user()
             end
+        end
 
         @testset "authors" begin
             @test tpl(; authors=["a"]).authors == ["a"]