allow building sysimg seperately

src/build.jl

@@ -2,7 +2,12 @@ module PATH
 using Libdl
 using ..Comonicon
 
-project(m::Module, xs...) = joinpath(dirname(dirname(pathof(m))), xs...)
+function project(m::Module, xs...)
+    path = pathof(m)
+    path === nothing && return
+    return joinpath(dirname(dirname(path)), xs...)
+end
+
 project(xs...) = project(Comonicon, xs...)
 
 """
@@ -20,6 +25,16 @@ function default_sysimg()
     end
 end
 
+function default_sysimg(mod, name)
+    lib = project(mod, "deps", "lib", "lib$name.$(Libdl.dlext)")
+    if lib !== nothing && isfile(lib)
+        return lib
+    else
+        # fallback to try Comonicon sysimg
+        return default_sysimg()
+    end
+end
+
 """
     default_exename()
 
@@ -121,8 +136,9 @@ Install the CLI defined in module `mod` to the `bin`.
 - `compile`: julia compile level, can be [:yes, :no, :all, :min]
 - `optimize`: julia optimization level, default is 2.
 - `sysimg`: compile a system image using PackageCompiler or not, default is `false`.
-- `incremental`: PackageCompiler option.
-- `filter_stdlibs`: PackageCompiler option.
+- `incremental`: PackageCompiler option, default is `false`.
+- `filter_stdlibs`: PackageCompiler option, default is `false`.
+- `cpu_target`: PackageCompiler option. default is "native".
 - `lib_path`: the `lib` folder that stores the compiled system image, default is the `<project>/deps/lib`.
 """
 function install(
@@ -132,39 +148,25 @@ function install(
     exename = PATH.default_exename(),
     project = PATH.project(mod),
     sysimg::Bool = false,
+    sysimg_path = PATH.default_sysimg(mod, name),
     incremental::Bool = false,
     compile = nothing,
     filter_stdlibs = false,
     lib_path = PATH.project(mod, "deps", "lib"),
+    cpu_target = "native",
     optimize = 2,
 )
 
     if sysimg
-        if !ispath(lib_path)
-            @info "creating library path: $lib_path"
-            mkpath(lib_path)
-        end
-
-        precompile_jl = PATH.project(mod, "deps", "precompile.jl")
-        @info "generating precompile execution file: $precompile_jl"
-        open(precompile_jl, "w+") do f
-            print(f, precompile_script(mod))
-        end
-
-        @info "compile under project: $project"
-        @info "incremental: $incremental"
-        @info "filter stdlibs: $filter_stdlibs"
-        sysimg_path = PATH.project(mod, "deps", "lib", "lib$name.$(Libdl.dlext)")
-        create_sysimage(
-            nameof(mod);
-            sysimage_path = sysimg_path,
-            incremental = incremental,
-            project = project,
-            precompile_execution_file = precompile_jl,
-            filter_stdlibs = filter_stdlibs,
+        build(mod, name;
+            sysimg_path=sysimg_path,
+            incremental=incremental,
+            compile=compile,
+            filter_stdlibs=filter_stdlibs,
+            lib_path=lib_path,
+            cpu_target=cpu_target,
+            optimize=optimize
         )
-    else
-        sysimg_path = nothing
     end
 
     shadow = joinpath(bin, name * ".jl")
@@ -214,6 +216,49 @@ function Base.write(io::IO, x::EntryCommand)
     println(io, "command_main()")
 end
 
+"""
+    build(mod[, name=default_name(mod)]; kwargs...)
+
+Build system image for given CLI module. See also [`install`](@ref).
+"""
+function build(
+        mod, name=default_name(mod);
+        sysimg_path=PATH.default_sysimg(mod, name),
+        project = PATH.project(mod),
+        sysimg::Bool = false,
+        incremental::Bool = false,
+        compile = nothing,
+        filter_stdlibs = false,
+        lib_path = PATH.project(mod, "deps", "lib"),
+        cpu_target = "native",
+        optimize = 2,
+    )
+
+    if !ispath(lib_path)
+        @info "creating library path: $lib_path"
+        mkpath(lib_path)
+    end
+
+    precompile_jl = PATH.project(mod, "deps", "precompile.jl")
+    @info "generating precompile execution file: $precompile_jl"
+    open(precompile_jl, "w+") do f
+        print(f, precompile_script(mod))
+    end
+
+    @info "compile under project: $project"
+    @info "incremental: $incremental"
+    @info "filter stdlibs: $filter_stdlibs"
+    create_sysimage(
+        nameof(mod);
+        sysimage_path = sysimg_path,
+        incremental = incremental,
+        project = project,
+        precompile_execution_file = precompile_jl,
+        cpu_target = cpu_target,
+        filter_stdlibs = filter_stdlibs,
+    )
+end
+
 """
     build()
 

test/parse.jl

@@ -114,3 +114,7 @@ ArgParse example implemented in Comonicon.
     @test opt1 == "3"
     @test opt2 == 2
 end
+
+Comonicon.install(Dummy; bin=Comonicon.PATH.project("test", "bin"))
+@test isfile(Comonicon.PATH.project("test", "bin", "dummy"))
+@test isfile(Comonicon.PATH.project("test", "bin", "dummy.jl"))