How to Build and Test Decimal Conversion

Quick Start

The decimal conversion test is integrated into the Universal build system as part of the value<> internal tests.

Building the Test

# From the Universal root directory
cd <UNIVERSAL_ROOT>

# Create build directory if it doesn't exist
mkdir -p build
cd build

# Configure with CMake - enable internal number tests
cmake .. -DUNIVERSAL_BUILD_NUMBER_INTERNALS=ON

# Build the specific decimal test
make value_decimal

# Or build all value tests
make -j$(nproc)

Running the Test

# From the build directory
./internal/value/value_decimal

Alternative: Build Everything

# From Universal root
mkdir -p build && cd build

# Build all internal tests (includes decimal conversion)
cmake .. -DUNIVERSAL_BUILD_NUMBER_INTERNALS=ON
make -j$(nproc)

# Run all value tests
ctest -R value

# Or run just the decimal test
./internal/value/value_decimal

What Gets Built

When you enable UNIVERSAL_BUILD_NUMBER_INTERNALS=ON, CMake will build:

• value_decimal - Decimal conversion test (NEW!)
• value_api - API tests
• value_arithmetic_add - Arithmetic tests
• value_experiment - Experimental tests
• value_formatting - Formatting tests
• value_performance - Performance tests

Test Location

• Source: ./build/internal/value/decimal.cpp
• Headers:
  • <ROOT>/include/sw/universal/number/support/dragon.hpp
  • <ROOT>/include/sw/universal/number/support/decimal_converter.hpp
• Built executable: ./build/internal/value/value_decimal

Expected Output

When you run the test, you should see output like:

Testing Dragon algorithm basic functions...
1 * 2^3 = 8 (expected 8)
2 * 5^2 = 50 (expected 50)
...

Testing value<> to decimal conversion...
value<52>(1.0):
  Default:    1.000000
  Scientific: 1.0000000000e+00
  Fixed:      1.0000
...

Testing ioflags variations...
value<52>(123.456) with different flags:
  default:           123.456000
  showpos:           +123.456000
  scientific:        1.234560e+02
...

Troubleshooting

Problem: make value_decimal fails with “No rule to make target”

Solution: Make sure you ran cmake with the correct flag:

cmake .. -DUNIVERSAL_BUILD_NUMBER_INTERNALS=ON

Problem: Compilation errors about missing headers

Solution: The headers are already in place. Make sure you’re building from the Universal root directory.

Problem: Want to enable just this test

Solution: The CMake configuration automatically picks up all .cpp files in internal/value/. The test is included when you build value tests.

Integration with CI

To add this test to your continuous integration:

# In your .github/workflows or CI config
- name: Build and Test Decimal Conversion
  run: |
    cd build
    cmake .. -DUNIVERSAL_BUILD_NUMBER_INTERNALS=ON
    make value_decimal
    ./internal/value/value_decimal

Next Steps

After verifying the test works:

1. Create a similar test for blocktriple<> in /internal/blocktriple/conversion/decimal.cpp
2. Integrate the decimal_converter into actual number types (posit, cfloat, etc.)
3. Add regression tests with specific expected values
4. Add to CI pipeline

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Note: This follows Universal’s standard testing pattern where each .cpp file in a test directory becomes an executable via the compile_all() macro in CMakeLists.txt.