test: precompile @register_unit in an external module.

src/register_units.jl

@@ -1,6 +1,5 @@
 import .Units: UNIT_MAPPING, UNIT_SYMBOLS, UNIT_VALUES, _lazy_register_unit
-import .SymbolicUnits:
-    SymbolicDimensionsSingleton, SYMBOLIC_UNIT_VALUES, update_symbolic_unit_values!
+import .SymbolicUnits: update_external_symbolic_unit_value
 
 # Update the unit collections
 const UNIT_UPDATE_LOCK = Threads.SpinLock()
@@ -12,7 +11,7 @@ function update_all_values(name_symbol, unit)
         i = lastindex(ALL_VALUES)
         ALL_MAPPING[name_symbol] = i
         UNIT_MAPPING[name_symbol] = i
-        update_symbolic_unit_values!(name_symbol)
+        update_external_symbolic_unit_value(name_symbol)
     end
 end
 

src/symbolic_dimensions.jl

@@ -417,7 +417,17 @@ module SymbolicUnits
     update_symbolic_unit_values!(w::WriteOnceReadMany) = update_symbolic_unit_values!.(w._raw_data)
     update_symbolic_unit_values!(UNIT_SYMBOLS)
 
-    """
+    # Non-eval version of `update_symbolic_unit_values!` for registering units in
+    # an external module.
+    function update_external_symbolic_unit_value(unit)
+        unit = constructorof(DEFAULT_SYMBOLIC_QUANTITY_TYPE)(
+            DEFAULT_VALUE_TYPE(1.0),
+            SymbolicDimensionsSingleton{DEFAULT_DIM_BASE_TYPE}(unit)
+        )
+        push!(SYMBOLIC_UNIT_VALUES, unit)
+    end
+
+"""
         sym_uparse(raw_string::AbstractString)
 
     Parse a string containing an expression of units and return the

test/precompile_test/ExternalUnitRegistration.jl

@@ -0,0 +1,21 @@
+module ExternalUnitRegistration
+
+using DynamicQuantities: @register_unit, @u_str, @us_str,
+    ALL_MAPPING, ALL_SYMBOLS,  DEFAULT_QUANTITY_TYPE,
+    DEFAULT_SYMBOLIC_QUANTITY_OUTPUT_TYPE, UNIT_SYMBOLS, UNIT_MAPPING
+using Test
+
+@register_unit Wb u"m^2*kg*s^-2*A^-1"
+
+@testset " Register Unit Inside a Module" begin
+    for collection in (UNIT_SYMBOLS, ALL_SYMBOLS, keys(ALL_MAPPING._raw_data), keys(UNIT_MAPPING._raw_data))
+        @test :Wb ∈ collection
+    end
+
+    w = u"Wb"
+    ws = us"Wb"
+    @test w isa DEFAULT_QUANTITY_TYPE
+    @test ws isa DEFAULT_SYMBOLIC_QUANTITY_OUTPUT_TYPE
+end
+
+end

test/unittests.jl

@@ -8,6 +8,7 @@ using DynamicQuantities: promote_quantity_on_quantity, promote_quantity_on_value
 using DynamicQuantities: UNIT_VALUES, UNIT_MAPPING, UNIT_SYMBOLS, ALL_MAPPING, ALL_SYMBOLS, ALL_VALUES
 using DynamicQuantities.SymbolicUnits: SYMBOLIC_UNIT_VALUES
 using DynamicQuantities: map_dimensions
+using DynamicQuantities: _register_unit
 using Ratios: SimpleRatio
 using SaferIntegers: SafeInt16
 using StaticArrays: SArray, MArray
@@ -1861,6 +1862,8 @@ all_map_count_before_registering = length(ALL_MAPPING)
 @register_unit MySV us"V"
 @register_unit MySV2 us"km/h"
 
+@test_throws "Unit `m` is already defined as `1.0 m`" esc(_register_unit(:m, u"s"))
+
 @testset "Register Unit" begin
     @test MyV === u"V"
     @test MyV == us"V"
@@ -1880,3 +1883,13 @@ all_map_count_before_registering = length(ALL_MAPPING)
         @test my_unit in ALL_SYMBOLS
     end
 end
+
+push!(LOAD_PATH, joinpath(@__DIR__, "precompile_test"))
+
+using ExternalUnitRegistration: Wb
+@testset "Type of Extenral Unit" begin
+    @test Wb isa DEFAULT_QUANTITY_TYPE
+    @test Wb/u"m^2*kg*s^-2*A^-1" == 1.0
+end
+
+pop!(LOAD_PATH)