core: add evaluation of conditions in evaluation of expressions with "eval_cond:" (closes #1582)

2 files changed, 26 insertions, 18 deletions

diff --git a/doc/it/includes/autogen_user_commands.it.adoc b/doc/it/includes/autogen_user_commands.it.adoc
index 097a190f2..4a35cbbcb 100644
--- a/doc/it/includes/autogen_user_commands.it.adoc
+++ b/doc/it/includes/autogen_user_commands.it.adoc
@@ -1336,24 +1336,25 @@ To force a string comparison, you can add double quotes around each expression,
 
 Some variables are replaced in expression, using the format ${variable}, variable can be, by order of priority:
   1. an evaluated sub-string (format: "eval:xxx")
-  2. a string with escaped chars (format: "esc:xxx" or "\xxx")
-  3. a string with chars to hide (format: "hide:char,string")
-  4. a string with max chars (format: "cut:max,suffix,string" or "cut:+max,suffix,string")
+  2. an evaluated condition (format: "eval_cond: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 string with max chars (format: "cut:max,suffix,string" or "cut:+max,suffix,string")
      or max chars displayed on screen (format: "cutscr:max,suffix,string" or "cutscr:+max,suffix,string")
-  5. a reversed string (format: "rev:xxx" or "revscr:xxx")
-  6. a repeated string (format: "repeat:count,string")
-  7. length of a string (format: "length:xxx" or "lengthscr:xxx")
-  8. a color (format: "color:xxx", see "Plugin API reference", function "color")
-  9. a modifier (format: "modifier:name,data,string")
-  10. an info (format: "info:name,arguments", arguments are optional)
-  11. a base 16/32/64 encoded/decoded string (format: "base_encode:base,xxx" or "base_decode:base,xxx")
-  12. current date/time (format: "date" or "date:format")
-  13. an environment variable (format: "env:XXX")
-  14. a ternary operator (format: "if:condition?value_if_true:value_if_false")
-  15. result of an expression with parentheses and operators + - * / // % ** (format: "calc:xxx")
-  16. an option (format: "file.section.option")
-  17. a local variable in buffer
-  18. a hdata name/variable (the value is automatically converted to string), by default "window" and "buffer" point to current window/buffer.
+  6. a reversed string (format: "rev:xxx" or "revscr:xxx")
+  7. a repeated string (format: "repeat:count,string")
+  8. length of a string (format: "length:xxx" or "lengthscr:xxx")
+  9. a color (format: "color:xxx", see "Plugin API reference", function "color")
+  10. a modifier (format: "modifier:name,data,string")
+  11. an info (format: "info:name,arguments", arguments are optional)
+  12. a base 16/32/64 encoded/decoded string (format: "base_encode:base,xxx" or "base_decode:base,xxx")
+  13. current date/time (format: "date" or "date:format")
+  14. an environment variable (format: "env:XXX")
+  15. a ternary operator (format: "if:condition?value_if_true:value_if_false")
+  16. result of an expression with parentheses and operators + - * / // % ** (format: "calc:xxx")
+  17. an option (format: "file.section.option")
+  18. a local variable in buffer
+  19. a hdata name/variable (the value is automatically converted to string), by default "window" and "buffer" point to current window/buffer.
 Format for hdata can be one of following:
   hdata.var1.var2...: start with a hdata (pointer must be known), and ask variables one after one (other hdata can be followed)
   hdata[list].var1.var2...: start with a hdata using a list, for example:
@@ -1364,6 +1365,7 @@ Format for hdata can be one of following:
 For name of hdata and variables, please look at "Plugin API reference", function "weechat_hdata_get".
 
 Examples (simple strings):
+  /eval -n ${eval_cond:${window.win_width}>100}  ==> 1
   /eval -n ${info:version}                       ==> 0.4.3
   /eval -n ${env:HOME}                           ==> /home/user
   /eval -n ${weechat.look.scroll_amount}         ==> 3
diff --git a/doc/it/weechat_plugin_api.it.adoc b/doc/it/weechat_plugin_api.it.adoc
index a7588feca..35f43922e 100644
--- a/doc/it/weechat_plugin_api.it.adoc
+++ b/doc/it/weechat_plugin_api.it.adoc
@@ -2294,7 +2294,7 @@ str3 = weechat.string_input_for_buffer("//test")  # "/test"
 
 // TRANSLATION MISSING
 _WeeChat ≥ 0.4.0, updated in 0.4.2, 0.4.3, 1.0, 1.1, 1.2, 1.3, 1.6, 1.8, 2.0,
-2.2, 2.3, 2.7 and 2.9._
+2.2, 2.3, 2.7, 2.9 and 3.1._
 
 // TRANSLATION MISSING
 Evaluate an expression and return result as a string.
@@ -2631,6 +2631,12 @@ expanded to last):
  `+19:02:45+` (with colors if there are color codes in the option
  weechat.look.buffer_time_format)
 
+| `+${eval_cond:xxx}+` +
+  _(WeeChat ≥ 3.1)_ |
+  String to evaluate as condition. |
+  `+${eval_cond:${window.win_width} > 100}+` |
+  `+1+`
+
 | `+${esc:xxx}+` +
   `+${\xxx}+` +
   _(WeeChat ≥ 1.0)_ |