core: add cut of string in evaluation of expressions

The syntax is: ${cut:max,suffix,string}.
The string is cut after max chars. If the string is cut, the optional suffix is
added after.

doc/en/weechat_plugin_api.en.adoc

@@ -2035,11 +2035,19 @@ expanded to last):
   `+prefix<TAB>message+` +
   `+©+`
 
-| `+${hide:x,value}+` |
-  String with hidden chars (all chars in `value` replaced by `x`). |
+| `+${hide:x,string}+` |
+  String with hidden chars (all chars in `string` replaced by `x`). |
   `+${hide:*,password}+` |
   `+********+`
 
+| `+${cut:max,suffix,string}+` +
+  (_WeeChat ≥ 1.8_) |
+  String with `max` chars displayed, and optional `suffix` if string is cut. |
+  `+${cut:4,…,this is a test}+` +
+  `+${cut:2,>>,àéçôî}+` |
+  `+this…+` +
+  `+àé>>+`
+
 | `+${re:N}+` |
   Regex captured group: `0` = whole string matching, `1` to `99` = group
   captured, `+++` = last group captured. |

doc/fr/weechat_plugin_api.fr.adoc

@@ -2077,12 +2077,20 @@ première étendue à la dernière) :
   `+préfixe<TAB>message+` +
   `+©+`
 
-| `+${hide:x,valeur}+` |
-  Chaîne avec les caractères masqués (tous les caractères dans `valeur`
-  remplacés par `x`. |
+| `+${hide:x,chaîne}+` |
+  Chaîne avec les caractères masqués (tous les caractères dans `chaîne`
+  remplacés par `x`). |
   `+${hide:*,mot_de_passe}+` |
   `+************+`
 
+| `+${cut:max,suffixe,chaîne}+` +
+  (_WeeChat ≥ 1.8_) |
+  Chaîne avec `max` caractères affichés, et un `suffixe` facultatif si la chaîne est coupée. |
+  `+${cut:4,…,ceci est un test}+` +
+  `+${cut:2,>>,àéçôî}+` |
+  `+ceci…+` +
+  `+àé>>+`
+
 | `+${re:N}+` |
   Groupe regex capturé : `0` = toute la chaîne correspondante,
   `1` à `99` = groupe capturé, `+++` = dernier groupe capturé. |

doc/it/weechat_plugin_api.it.adoc

@@ -2113,11 +2113,19 @@ expanded to last):
   `+prefix<TAB>message+` +
   `+©+`
 
-| `+${hide:x,value}+` |
-  String with hidden chars (all chars in `value` replaced `x`). |
+| `+${hide:x,string}+` |
+  String with hidden chars (all chars in `string` replaced `x`). |
   `+${hide:*,password}+` |
   `+********+`
 
+| `+${cut:max,suffix,string}+` +
+  (_WeeChat ≥ 1.8_) |
+  String with `max` chars displayed, and optional `suffix` if string is cut. |
+  `+${cut:4,…,this is a test}+` +
+  `+${cut:2,>>,àéçôî}+` |
+  `+this…+` +
+  `+àé>>+`
+
 | `+${re:N}+` |
   Regex captured group: `0` = whole string matching, `1` to `99` = group
   captured, `+++` = last group captured. |

doc/ja/weechat_plugin_api.ja.adoc

@@ -2041,11 +2041,20 @@ char *weechat_string_eval_expression (const char *expr,
   `+prefix<TAB>message+` +
   `+©+`
 
-| `+${hide:x,value}+` |
-  隠す文字を含むテキスト (`value` に含まれる文字をすべて `x` で置換) |
+| `+${hide:x,string}+` |
+  隠す文字を含むテキスト (`string` に含まれる文字をすべて `x` で置換) |
   `+${hide:*,password}+` |
  `+********+`
 
+// TRANSLATION MISSING
+| `+${cut:max,suffix,string}+` +
+  (_WeeChat バージョン 1.8 以上で利用可_) |
+  String with `max` chars displayed, and optional `suffix` if string is cut. |
+  `+${cut:4,…,this is a test}+` +
+  `+${cut:2,>>,àéçôî}+` |
+  `+this…+` +
+  `+àé>>+`
+
 | `+${re:N}+` |
   正規表現のキャプチャグループ: `0` = マッチするすべての文字列、`1` から `99` =
   キャプチャされたグループ、`+++` = 最後にキャプチャされたグループ |

src/core/wee-eval.c

@@ -295,15 +295,16 @@ end:
  *   2. a string to evaluate (format: eval:xxx)
  *   3. a string with escaped chars (format: esc:xxx or \xxx)
  *   4. a string with chars to hide (format: hide:char,string)
- *   5. a regex group captured (format: re:N (0.99) or re:+)
- *   6. a color (format: color:xxx)
- *   7. an info (format: info:name,arguments)
- *   8. current date/time (format: date or date:xxx)
- *   9. an environment variable (format: env:XXX)
- *  10. a ternary operator (format: if:condition?value_if_true:value_if_false)
- *  11. an option (format: file.section.option)
- *  12. a buffer local variable
- *  13. a hdata variable (format: hdata.var1.var2 or hdata[list].var1.var2
+ *   5. a string with max chars (format: cut:max,suffix,string)
+ *   6. a regex group captured (format: re:N (0.99) or re:+)
+ *   7. a color (format: color:xxx)
+ *   8. an info (format: info:name,arguments)
+ *   9. current date/time (format: date or date:xxx)
+ *  10. an environment variable (format: env:XXX)
+ *  11. a ternary operator (format: if:condition?value_if_true:value_if_false)
+ *  12. an option (format: file.section.option)
+ *  13. a buffer local variable
+ *  14. a hdata variable (format: hdata.var1.var2 or hdata[list].var1.var2
  *                        or hdata[ptr].var1.var2)
  *
  * See /help in WeeChat for examples.
@@ -404,7 +405,37 @@ eval_replace_vars_cb (void *data, const char *text)
         return (hidden_string) ? hidden_string : strdup ("");
     }
 
-    /* 5. regex group captured */
+    /*
+     * 5. cut chars: max number of chars, and add an optional suffix when the
+     * string is cut
+     */
+    if (strncmp (text, "cut:", 4) == 0)
+    {
+        pos = strchr (text + 4, ',');
+        if (!pos)
+            return strdup ("");
+        pos2 = strchr (pos + 1, ',');
+        if (!pos2)
+            return strdup ("");
+        tmp = strndup (text + 4, pos - text - 4);
+        if (!tmp)
+            return strdup ("");
+        number = strtol (tmp, &error, 10);
+        if (!error || error[0] || (number < 0))
+        {
+            free (tmp);
+            return strdup ("");
+        }
+        free (tmp);
+        tmp = strndup (pos + 1, pos2 - pos - 1);
+        if (!tmp)
+            return strdup ("");
+        value = string_cut (pos2 + 1, number, tmp);
+        free (tmp);
+        return value;
+    }
+
+    /* 6. regex group captured */
     if (strncmp (text, "re:", 3) == 0)
     {
         if (eval_regex && eval_regex->result)
@@ -427,7 +458,7 @@ eval_replace_vars_cb (void *data, const char *text)
         return strdup ("");
     }
 
-    /* 6. color code */
+    /* 7. color code */
     if (strncmp (text, "color:", 6) == 0)
     {
         ptr_value = gui_color_search_config (text + 6);
@@ -437,7 +468,7 @@ eval_replace_vars_cb (void *data, const char *text)
         return strdup ((ptr_value) ? ptr_value : "");
     }
 
-    /* 7. info */
+    /* 8. info */
     if (strncmp (text, "info:", 5) == 0)
     {
         ptr_value = NULL;
@@ -457,7 +488,7 @@ eval_replace_vars_cb (void *data, const char *text)
         return strdup ((ptr_value) ? ptr_value : "");
     }
 
-    /* 8. current date/time */
+    /* 9. current date/time */
     if ((strncmp (text, "date", 4) == 0) && (!text[4] || (text[4] == ':')))
     {
         date = time (NULL);
@@ -470,7 +501,7 @@ eval_replace_vars_cb (void *data, const char *text)
         return strdup ((rc > 0) ? str_value : "");
     }
 
-    /* 9. environment variable */
+    /* 10. environment variable */
     if (strncmp (text, "env:", 4) == 0)
     {
         ptr_value = getenv (text + 4);
@@ -478,7 +509,7 @@ eval_replace_vars_cb (void *data, const char *text)
             return strdup (ptr_value);
     }
 
-    /* 10: ternary operator: if:condition?value_if_true:value_if_false */
+    /* 11: ternary operator: if:condition?value_if_true:value_if_false */
     if (strncmp (text, "if:", 3) == 0)
     {
         value = NULL;
@@ -542,7 +573,7 @@ eval_replace_vars_cb (void *data, const char *text)
         return (value) ? value : strdup ("");
     }
 
-    /* 11. option: if found, return this value */
+    /* 12. option: if found, return this value */
     if (strncmp (text, "sec.data.", 9) == 0)
     {
         ptr_value = hashtable_get (secure_hashtable_data, text + 9);
@@ -575,7 +606,7 @@ eval_replace_vars_cb (void *data, const char *text)
         }
     }
 
-    /* 12. local variable in buffer */
+    /* 13. local variable in buffer */
     ptr_buffer = hashtable_get (pointers, "buffer");
     if (ptr_buffer)
     {
@@ -584,7 +615,7 @@ eval_replace_vars_cb (void *data, const char *text)
             return strdup (ptr_value);
     }
 
-    /* 13. hdata */
+    /* 14. hdata */
     value = NULL;
     hdata_name = NULL;
     list_name = NULL;

src/core/wee-string.c

@@ -51,6 +51,7 @@
 #include "wee-eval.h"
 #include "wee-hashtable.h"
 #include "wee-utf8.h"
+#include "../gui/gui-chat.h"
 #include "../gui/gui-color.h"
 #include "../plugins/plugin.h"
 
@@ -91,6 +92,45 @@ string_strndup (const char *string, int length)
     return result;
 }
 
+/*
+ * Cuts a string after max "length" chars, adds an optional suffix
+ * after the string if it is cut.
+ *
+ * Note: result must be freed after use.
+ */
+
+char *
+string_cut (const char *string, int length, const char *cut_suffix)
+{
+    int length_result, length_cut_suffix;
+    char *result;
+    const char *ptr_string;
+
+    ptr_string = gui_chat_string_add_offset (string, length);
+    if (!ptr_string[0])
+    {
+        /* no cut */
+        return strdup (string);
+    }
+
+    if (cut_suffix && cut_suffix[0])
+    {
+        length_cut_suffix = strlen (cut_suffix);
+        length_result = (ptr_string - string) + length_cut_suffix + 1;
+        result = malloc (length_result);
+        if (!result)
+            return NULL;
+        memcpy (result, string, ptr_string - string);
+        memcpy (result + (ptr_string - string), cut_suffix,
+                length_cut_suffix + 1);
+        return result;
+    }
+    else
+    {
+        return string_strndup (string, ptr_string - string);
+    }
+}
+
 /*
  * Converts string to lower case (locale independent).
  */

src/core/wee-string.h

@@ -36,6 +36,8 @@ struct t_string_dyn
 struct t_hashtable;
 
 extern char *string_strndup (const char *string, int length);
+extern char *string_cut (const char *string, int length,
+                         const char *cut_suffix);
 extern void string_tolower (char *string);
 extern void string_toupper (char *string);
 extern int string_strcasecmp (const char *string1, const char *string2);

tests/unit/core/test-eval.cpp

@@ -218,6 +218,16 @@ TEST(Eval, EvalExpression)
     WEE_CHECK_EVAL("********", "${hide:*,password}");
     WEE_CHECK_EVAL("\u2603\u2603\u2603", "${hide:${esc:\u2603},abc}");
 
+    /* test cut of chars */
+    WEE_CHECK_EVAL("", "${cut:0,,}");
+    WEE_CHECK_EVAL("", "${cut:0,+,}");
+    WEE_CHECK_EVAL("", "${cut:0,,test}");
+    WEE_CHECK_EVAL("+", "${cut:0,+,test}");
+    WEE_CHECK_EVAL("te", "${cut:2,,test}");
+    WEE_CHECK_EVAL("te+", "${cut:2,+,test}");
+    WEE_CHECK_EVAL("éà", "${cut:2,,éàô}");
+    WEE_CHECK_EVAL("éà+", "${cut:2,+,éàô}");
+
     /* test color */
     WEE_CHECK_EVAL(gui_color_get_custom ("green"), "${color:green}");
     WEE_CHECK_EVAL(gui_color_get_custom ("*214"), "${color:*214}");