tool: improve config error messaging

- make sure that errors for specific options in config files identify
  the file, line number and shows the error about the correct option

- improve some error message wording

- add warning for leading single quote of arguments in config files
  (verified in test 1712)

- adjust test error outputs accordingly

test1712 introduces mode=warn

Use the mode="warn" attribute if the output curl warning output, as it
then makes the check without newlines and the prefix to better handle
that the lines may wrap at different points depending on the lengths of
the lines and terminal width.

Fixes #20598
Closes #20666

tests/data/Makefile.am

@@ -229,7 +229,7 @@ test1670 test1671 \
 test1680 test1681 test1682 test1683 \
 \
 test1700 test1701 test1702 test1703 test1704 test1705 test1706 test1707 \
-test1708 test1709 test1710 test1711 \
+test1708 test1709 test1710 test1711 test1712 \
 \
 test1800 test1801 test1802 test1847 test1848 \
 \

tests/data/test1712

@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="US-ASCII"?>
+<testcase>
+<info>
+<keywords>
+HTTP
+--config
+</keywords>
+</info>
+
+# Server-side
+<reply>
+<data crlf="headers">
+HTTP/1.1 200 OK
+Date: Tue, 09 Nov 2010 14:49:00 GMT
+Server: test-server/fake
+Last-Modified: Tue, 13 Jun 2000 12:10:00 GMT
+ETag: "21025-dc7-39462498"
+Accept-Ranges: bytes
+Content-Length: 6
+Connection: close
+Content-Type: text/html
+Funny-head: yesyes
+
+-foo-
+</data>
+</reply>
+
+# Client-side
+<client>
+<server>
+http
+</server>
+<name>
+config file with argument using single quotes
+</name>
+<file name="%LOGDIR/config">
+data = 'arg-with-quote'
+</file>
+<command>
+http://%HOSTIP:%HTTPPORT/%TESTNUMBER --config %LOGDIR/config --silent
+</command>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<protocol crlf="yes" nonewline="yes">
+POST /%TESTNUMBER HTTP/1.1
+Host: %HOSTIP:%HTTPPORT
+User-Agent: curl/%VERSION
+Accept: */*
+Content-Length: 16
+Content-Type: application/x-www-form-urlencoded
+
+'arg-with-quote'
+</protocol>
+<stderr mode="warn">
+Warning: %LOGDIR/config:1 Option 'data' uses argument with leading single quote.%SP
+It is probably a mistake. Consider double quotes.
+</stderr>
+</verify>
+</testcase>

tests/data/test459

@@ -54,8 +54,8 @@ Content-Type: application/x-www-form-urlencoded
 arg
 </protocol>
 <stderr mode="text">
-Warning: %LOGDIR/config:1: warning: 'data' uses unquoted whitespace. This may%SP
-Warning: cause side-effects. Consider double quotes.
+Warning: %LOGDIR/config:1 Option 'data' uses argument with unquoted whitespace.%SP
+Warning: This may cause side-effects. Consider double quotes.
 </stderr>
 </verify>
 </testcase>