Merge pull request #133 from edgar-bonet/many-digits

aentinger · web-flow · commit 2af4a9c721f9 · 2021-01-25T16:15:51.000+01:00
Test Stream::parseFloat() with many input digits
diff --git a/api/Stream.cpp b/api/Stream.cpp
@@ -162,9 +162,9 @@ float Stream::parseFloat(LookaheadMode lookahead, char ignore)
 {
   bool isNegative = false;
   bool isFraction = false;
-  long value = 0;
+  double value = 0.0;
   int c;
-  float fraction = 1.0;
+  double fraction = 1.0;
 
   c = peekNextDigit(lookahead, true);
     // ignore non numeric leading characters
@@ -179,9 +179,12 @@ float Stream::parseFloat(LookaheadMode lookahead, char ignore)
     else if (c == '.')
       isFraction = true;
     else if(c >= '0' && c <= '9')  {      // is c a digit?
-      value = value * 10 + c - '0';
-      if(isFraction)
-         fraction *= 0.1;
+      if(isFraction) {
+        fraction *= 0.1;
+        value = value + fraction * (c - '0');
+      } else {
+        value = value * 10 + c - '0';
+      }
     }
     read();  // consume the character we got with peek
     c = timedPeek();
@@ -190,10 +193,8 @@ float Stream::parseFloat(LookaheadMode lookahead, char ignore)
 
   if(isNegative)
     value = -value;
-  if(isFraction)
-    return value * fraction;
-  else
-    return value;
+
+  return value;
 }
 
 // read characters from stream into buffer
diff --git a/test/src/Stream/test_parseFloat.cpp b/test/src/Stream/test_parseFloat.cpp
@@ -10,6 +10,8 @@
 
 #include <StreamMock.h>
 
+#include <float.h>
+
 /**************************************************************************************
  * TEST CODE
  **************************************************************************************/
@@ -43,6 +45,16 @@ TEST_CASE ("Testing parseFloat(LookaheadMode lookahead = SKIP_ALL, char ignore =
     mock << "\r\n\t 12.34";
     REQUIRE(mock.parseFloat() == 12.34f);
   }
+  WHEN ("A float is provided with too many digits after the decimal point")
+  {
+    mock << "3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245870064";
+    REQUIRE(mock.parseFloat() == Approx(3.141592654f));
+  }
+  WHEN ("A float is larger than LONG_MAX")
+  {
+    mock << "602200000000000000000000.00";
+    REQUIRE(mock.parseFloat() == Approx(6.022e23f));
+  }
 }
 
 TEST_CASE ("Testing parseFloat(LookaheadMode lookahead = SKIP_NONE, char ignore = NO_IGNORE_CHAR)", "[Stream-parseFloat-02]")
