From: David Wells <wellsd2@rpi.edu>
Date: Thu, 3 Dec 2015 03:53:08 +0000 (-0500)
Subject: Modify Utilities::trim to remove all whitespace.
X-Git-Tag: v8.4.0-rc2~179^2~1
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=84054894a9e53786e595ad0895256946f19ef7ab;p=dealii.git

Modify Utilities::trim to remove all whitespace.

This fixes issue #1691, where a ParameterHandler could not read files
with DOS line endings because Utilities::trim did not discard the '\r'
characters.
---

diff --git a/doc/news/changes.h b/doc/news/changes.h
index e8afbbf7ea..bb86ebe937 100644
--- a/doc/news/changes.h
+++ b/doc/news/changes.h
@@ -38,6 +38,13 @@ inconvenience this causes.
 </p>
 
 <ol>
+  <li> Changed: The function <code>Utilities::trim</code> now removes general
+  white space characters, such as '<tt>\\r</tt>' and '<tt>\\n</tt>', as well as
+  space characters.
+  <br>
+  (David Wells, 2015/12/05)
+  </li>
+
   <li> Removed: Previously deprecated global instance multithread_info of
   MultithreadInfo has been removed (all members of this class are static
   so there is no reason to use/create an instance). The deprecated
diff --git a/include/deal.II/base/utilities.h b/include/deal.II/base/utilities.h
index 582eb6e0dc..1ac3b2ec70 100644
--- a/include/deal.II/base/utilities.h
+++ b/include/deal.II/base/utilities.h
@@ -199,9 +199,12 @@ namespace Utilities
                                 const std::string &to);
 
   /**
-   * Return a string with all spaces at the beginning and end of @p input removed.
+   * Return a string with all standard whitespace characters (including
+   * '<tt>\\t</tt>', '<tt>\\n</tt>', and '<tt>\\r</tt>') at the beginning and
+   * end of @p input removed.
    */
-  std::string trim(const std::string &input);
+  std::string
+  trim(const std::string &input);
 
   /**
    * Generate a random number from a normalized Gaussian probability
diff --git a/source/base/utilities.cc b/source/base/utilities.cc
index 4c2961b94a..9de4a062c6 100644
--- a/source/base/utilities.cc
+++ b/source/base/utilities.cc
@@ -25,6 +25,7 @@ DEAL_II_DISABLE_EXTRA_DIAGNOSTICS
 DEAL_II_ENABLE_EXTRA_DIAGNOSTICS
 
 #include <algorithm>
+#include <cctype>
 #include <cerrno>
 #include <cmath>
 #include <cstddef>
@@ -115,14 +116,30 @@ namespace Utilities
   std::string
   trim(const std::string &input)
   {
-    std::string::size_type start_idx = input.find_first_not_of(" ");
-    if (start_idx == std::string::npos)
-      return "";
+    std::string::size_type left = 0;
+    std::string::size_type right = input.size() - 1;
 
-    std::string::size_type end_idx = input.find_last_not_of(" ");
-    return std::string( input, start_idx, end_idx+1-start_idx);
+    for (; left < input.size(); ++left)
+      {
+        if (!std::isspace(input[left]))
+          {
+            break;
+          }
+      }
+
+    for (; right >= left; --right)
+      {
+        if (!std::isspace(input[right]))
+          {
+            break;
+          }
+      }
+
+    return std::string(input, left, right - left + 1);
   }
 
+
+
   std::string
   dim_string(const int dim, const int spacedim)
   {
diff --git a/tests/base/utilities_trim.cc b/tests/base/utilities_trim.cc
index 4a0a0972ee..09e66c5022 100644
--- a/tests/base/utilities_trim.cc
+++ b/tests/base/utilities_trim.cc
@@ -14,35 +14,36 @@
 // ---------------------------------------------------------------------
 
 
-// test Utilities::trim
-
-#include "../tests.h"
-#include <iomanip>
-#include <iomanip>
-#include <fstream>
-#include <cmath>
+// test Utilities::trim. Note that deallog does not like being given '\n's in
+// the middle of strings, so the output file is almost empty.
 
+#include <deal.II/base/logstream.h>
 #include <deal.II/base/utilities.h>
 
+#include <fstream>
+
+using namespace dealii;
 
 void check(const std::string &input, const std::string &expected)
 {
-  deallog << "trim(\"" << input << "\") = \"" << Utilities::trim(input) << "\"" << std::endl;
-  Assert(Utilities::trim(input) == expected, ExcInternalError());
+  AssertThrow(Utilities::trim(input) == expected, ExcInternalError());
 }
 
 
 
 void test ()
 {
-  check("Hello World", "Hello World");
+  check("\r\nHello World\r\n\r", "Hello World");
   check("", "");
   check(" ", "");
   check("    ", "");
-  check("  middle   ", "middle");
-  check("left   ", "left");
-  check("  right", "right");
-  check("  multiple  words with spaces  ", "multiple  words with spaces");
+  check("  \r\n\v\t\r\n\f  ", "");
+  check("  \rmiddle\r\n   ", "middle");
+  check("left\v\t\r\n   ", "left");
+  check("  \n\v\f\r\nright", "right");
+  check(" \t\v\f\t\r\n\r multiple  words with spaces  \v\f\n", "multiple  words with spaces");
+
+  deallog << "OK" << std::endl;
 }
 
 
diff --git a/tests/base/utilities_trim.output b/tests/base/utilities_trim.output
index 270fa06572..0fd8fc12f0 100644
--- a/tests/base/utilities_trim.output
+++ b/tests/base/utilities_trim.output
@@ -1,9 +1,2 @@
 
-DEAL::trim("Hello World") = "Hello World"
-DEAL::trim("") = ""
-DEAL::trim(" ") = ""
-DEAL::trim("    ") = ""
-DEAL::trim("  middle   ") = "middle"
-DEAL::trim("left   ") = "left"
-DEAL::trim("  right") = "right"
-DEAL::trim("  multiple  words with spaces  ") = "multiple  words with spaces"
+DEAL::OK