AK: Add formatters for floating point numbers.

1 files changed, 23 insertions, 0 deletions

diff --git a/AK/Tests/TestFormat.cpp b/AK/Tests/TestFormat.cpp
index d31858e9ec..23431cf730 100644
--- a/AK/Tests/TestFormat.cpp
+++ b/AK/Tests/TestFormat.cpp
@@ -235,4 +235,27 @@ TEST_CASE(file_descriptor)
     fclose(file);
 }
 
+TEST_CASE(floating_point_numbers)
+{
+    EXPECT_EQ(String::formatted("{}", 1.12), "1.120000");
+    EXPECT_EQ(String::formatted("{}", 1.), "1.000000");
+    EXPECT_EQ(String::formatted("{:.3}", 1.12), "1.120");
+    EXPECT_EQ(String::formatted("{:.1}", 1.12), "1.1");
+    EXPECT_EQ(String::formatted("{}", -1.12), "-1.120000");
+
+    // FIXME: There is always the question what we mean with the width field. Do we mean significant digits?
+    //        Do we mean the whole width? This is what was the simplest to implement:
+    EXPECT_EQ(String::formatted("{:x>5.1}", 1.12), "xx1.1");
+}
+
+TEST_CASE(no_precision_no_trailing_number)
+{
+    EXPECT_EQ(String::formatted("{:.0}", 0.1), "0.");
+}
+
+TEST_CASE(yay_this_implementation_sucks)
+{
+    EXPECT_EQ(String::formatted("{:.0}", .99999999999), "0.");
+}
+
 TEST_MAIN(Format)