support/testing: new bc runtime test

Signed-off-by: Julien Olivain <ju.o@free.fr>
[yann.morin.1998@free.fr: tweak hex number]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

DEVELOPERS

@@ -1760,6 +1760,7 @@ F:	support/testing/tests/package/sample_python_spake2.py
 F:	support/testing/tests/package/test_acpica.py
 F:	support/testing/tests/package/test_acpica/
 F:	support/testing/tests/package/test_apache.py
+F:	support/testing/tests/package/test_bc.py
 F:	support/testing/tests/package/test_brotli.py
 F:	support/testing/tests/package/test_bzip2.py
 F:	support/testing/tests/package/test_compressor_base.py

support/testing/tests/package/test_bc.py

@@ -0,0 +1,62 @@
+import math
+import os
+
+import infra.basetest
+
+
+class TestBc(infra.basetest.BRTest):
+    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
+        """
+        BR2_PACKAGE_BC=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """
+
+    def test_run(self):
+        cpio_file = os.path.join(self.builddir, "images", "rootfs.cpio")
+        self.emulator.boot(arch="armv5",
+                           kernel="builtin",
+                           options=["-initrd", cpio_file])
+        self.emulator.login()
+
+        # Check the program executes.
+        self.assertRunOk("bc --version")
+
+        # We check a square root function of a number slightly larger
+        # than 32 bits.
+        value = 123456
+        squared_value = value ** 2
+        bc_expr = f"sqrt({squared_value})"
+        cmd = f"echo '{bc_expr}' | bc"
+        output, exit_code = self.emulator.run(cmd)
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(int(output[0]), value)
+
+        # Perform an integer exponentiation producing a large number.
+        base = 3
+        exponent = 4567
+        expected_value = base ** exponent
+        bc_expr = f"{base} ^ {exponent}"
+        cmd = f"echo '{bc_expr}' | BC_LINE_LENGTH=0 bc"
+        output, exit_code = self.emulator.run(cmd)
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(int(output[0]), expected_value)
+
+        # Test a basic output base conversion of a large number.
+        hex_str = "DEADBEEF0000ABADC0DE00008BADF00D"
+        hex_base = 16
+        value = int(hex_str, base=hex_base)
+        bc_expr = f"obase={hex_base} ; {value}"
+        cmd = f"echo '{bc_expr}' | bc"
+        output, exit_code = self.emulator.run(cmd)
+        self.assertEqual(exit_code, 0)
+        self.assertEqual(output[0], hex_str)
+
+        # Test a floating point computation by estimating Pi. Since we
+        # use the bc arc-tangent a() function, we need the '-l'
+        # option.
+        bc_expr = "4 * a(1)"
+        cmd = f"echo '{bc_expr}' | bc -l"
+        output, exit_code = self.emulator.run(cmd)
+        self.assertEqual(exit_code, 0)
+        self.assertAlmostEqual(float(output[0]), math.pi, places=16)