From faeafc9d652ba6caa350ca95dff14408b036ccfb Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Wed, 1 Aug 2012 23:43:34 +0300
Subject: [PATCH] Fix several corner case bugs in lexical_cast

---
 source/strings/fmt.cpp         |  3 +++
 source/strings/lexicalcast.cpp | 25 ++++++++++++++++++-------
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/source/strings/fmt.cpp b/source/strings/fmt.cpp
index ec7a782..07484dd 100644
--- a/source/strings/fmt.cpp
+++ b/source/strings/fmt.cpp
@@ -26,6 +26,9 @@ void Fmt::parse(const char *s)
 			break;
 	}
 
+	if(align==LEFT)
+		fillc = ' ';
+
 	wd = 0;
 	for(; *f; ++f)
 	{
diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 6a226e1..ab83b11 100644
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -237,7 +237,7 @@ string flt_to_str(T v, const Fmt &f)
 	if(w>=10)
 	{
 		long double div = 1;
-		while(div*10<w)
+		while(div*10<=w)
 		{
 			++exp;
 			div *= 10;
@@ -257,6 +257,7 @@ string flt_to_str(T v, const Fmt &f)
 
 	// Decide how to format the number
 	unsigned digits;
+	unsigned leading_zeroes = 0;
 	unsigned point = 1;
 	bool showexp = false;
 	if(mode==Fmt::FIXED)
@@ -279,15 +280,16 @@ string flt_to_str(T v, const Fmt &f)
 		}
 		else
 		{
-			point = max(exp, 0)+1;
 			if(exp<0)
-				digits += -exp;
+				leading_zeroes = -exp;
+			else
+				point = exp+1;
 		}
 	}
 
 	// Apply rounding
 	w += 5.0l/pow(10.0l, static_cast<long double>(digits));
-	if(w>10)
+	if(w>=10)
 	{
 		// Rounding bumped us to the next exponent, deal with it
 		w /= 10;
@@ -298,13 +300,19 @@ string flt_to_str(T v, const Fmt &f)
 		}
 		if(!showexp)
 		{
-			++digits;
-			++point;
+			if(mode==Fmt::FIXED)
+				++digits;
+			if(leading_zeroes)
+				--leading_zeroes;
+			else
+				++point;
 		}
 		else
 			++exp;
 	}
 
+	digits += leading_zeroes;
+
 	// Create a buffer and start from the end
 	unsigned size = max(f.get_width(), digits+8);
 	char *buf = new char[size];
@@ -326,14 +334,17 @@ string flt_to_str(T v, const Fmt &f)
 	{
 		if(i==point)
 			*mptr++ = '.';
-		if(showexp || static_cast<int>(i)>=-exp)
+		if(!leading_zeroes)
 		{
 			int digit = static_cast<int>(w);
 			*mptr++ = '0'+digit;
 			w = (w-digit)*10;
 		}
 		else
+		{
 			*mptr++ = '0';
+			--leading_zeroes;
+		}
 	}
 
 	if(f.get_showpoint())
-- 
2.43.0