issue# 3: added initial support for screen width detection

2 files changed, 29 insertions, 11 deletions

diff --git a/source/1.0/src/shflags b/source/1.0/src/shflags
index 689f564..33a282a 100644
--- a/source/1.0/src/shflags
+++ b/source/1.0/src/shflags
@@ -442,15 +442,22 @@ _flags_itemInList()
   return ${flags_return}
 }
 
-# Returns the length of a string.
+# Returns the width of the current screen.
 #
-# Args:
-#   str: string: string to determine length of
 # Output:
-#   integer: length of string
-_flags_strlen()
+#   integer: width in columns of the current screen.
+_flags_screenColumns()
 {
-  echo "$1" |awk '{print length($0)}'
+  _flags_size_=`stty size 2>/dev/null`
+  if [ $? -eq ${FLAGS_TRUE} ]; then
+    _flags_cols_=`expr "${_flags_size_}" : '[0-9]* \([0-9]*\)'`
+  else
+    # TODO(kward): support 'tput cols' as well, if possible. be warned that it
+    # doesn't work when put inside backticks (i.e. a sub-shell).
+    _flags_cols_=80
+  fi
+  echo ${_flags_cols_}
+  unset _flags_cols_ _flags_size_
 }
 
 # Validate a boolean.
@@ -920,8 +927,9 @@ flags_help()
       _flags_defaultStr="(default: ${_flags_defaultStr})"
 
       _flags_helpStr="  ${_flags_flagStr}  ${_flags_help} ${_flags_defaultStr}"
-      _flags_helpStrLen=`_flags_strlen "${_flags_helpStr}"`
-      if [ ${_flags_helpStrLen} -lt 80 ]; then
+      _flags_helpStrLen=`expr "${_flags_helpStr}" : '.*'`
+      flags_screenCols_=`_flags_screenColumns`
+      if [ ${_flags_helpStrLen} -lt ${flags_screenCols_} ]; then
         echo "${_flags_helpStr}" >&2
       else
         _flags_emptyStr="`echo ${_flags_flagStr} |sed 's/./ /g'`"
diff --git a/source/1.0/src/shflags_test_private.sh b/source/1.0/src/shflags_test_private.sh
index 9e28c8b..db508a5 100755
--- a/source/1.0/src/shflags_test_private.sh
+++ b/source/1.0/src/shflags_test_private.sh
@@ -52,7 +52,15 @@ testItemInList()
   assertFalse 'empty lists should not match' $?
 }
 
-testValidateBoolean() {
+testScreenColumns()
+{
+  cols=`_flags_screenColumns`
+  value=`expr "${cols}" : '\([0-9]*\)'`
+  assertNotNull "unexpected screen width (${cols})" "${value}"
+}
+
+testValidateBoolean()
+{
   # valid values
   for value in ${TH_BOOL_VALID}; do
     _flags_validateBoolean "${value}"
@@ -66,7 +74,8 @@ testValidateBoolean() {
   done
 }
 
-testValidateFloat() {
+testValidateFloat()
+{
   # valid values
   for value in ${TH_INT_VALID} ${TH_FLOAT_VALID}; do
     _flags_validateFloat "${value}"
@@ -80,7 +89,8 @@ testValidateFloat() {
   done
 }
 
-testValidateInteger() {
+testValidateInteger()
+{
   # valid values
   for value in ${TH_INT_VALID}; do
     _flags_validateInteger "${value}"