Add support for embedded sh commandsHEADmain

3 files changed, 61 insertions, 23 deletions

diff --git a/doc/preseed.txt b/doc/preseed.txt
index 5603423..71903f2 100644
--- a/doc/preseed.txt
+++ b/doc/preseed.txt
@@ -6,5 +6,15 @@ some of its derivatives. As the preseed files typically either have "txt" or
 simply no file extension, filetype detection relies on their first line being
 `#_preseed_V1`.
 
-                                                        *preseed-settings*
-This plugin doesn't have any settings.
+                               *preseed_add_sh_pattern* *preseed-settings*
+
+Any custom questions can be set to have their arguments set as shell, just like
+for `preseed/include_command` and friends, by setting 'preseed_add_sh_pattern'.
+
+e.g.:
+
+  let g:preseed_add_sh_pattern = '\(site_pkg/some_question\|my_pkg/a_question\)
+
+Needing to set the pattern for any widely available package is to be considered
+a bug. Please report if required to override the pattern to match a question
+expecting a shell command argument for any package included in debian.
diff --git a/doc/tags b/doc/tags
index 8233d62..8207347 100644
--- a/doc/tags
+++ b/doc/tags
@@ -1,3 +1,4 @@
 ft-preseed-syntax	preseed.txt	/*ft-preseed-syntax*
 preseed-settings	preseed.txt	/*preseed-settings*
 preseed.txt	preseed.txt	/*preseed.txt*
+preseed_add_sh_pattern	preseed.txt	/*preseed_add_sh_pattern*
diff --git a/syntax/preseed.vim b/syntax/preseed.vim
index 4690280..5b41c74 100644
--- a/syntax/preseed.vim
+++ b/syntax/preseed.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language:	Debian preseed
 " Maintainer:	cos <cos>, https://www.netizen.se/#contact
-" Last Change:	2023 Nov 2
+" Last Change:	2023 Nov 10
 " Remark:	https://wiki.debian.org/DebianInstaller/Preseed
 
 " quit when a syntax file was already loaded
@@ -9,6 +9,17 @@ if exists('b:current_syntax')
   finish
 endif
 
+" Allow user defined questions to have their shell script argument highlighted
+" as sh. Please see ':help preseed_add_sh_pattern' for an example.
+let s:shell_question_pattern = '\(preseed/\(early_command\|include_command\|late_command\)\|partman/early_command\)'
+let shell_pattern_start='^\s*[[:alnum:]._-]\+\s\+'
+if exists('preseed_add_sh_pattern')
+  let shell_pattern_start ..= '\(' . s:shell_question_pattern . '\|' . preseed_add_sh_pattern . '\) string'
+else
+  let shell_pattern_start ..= s:shell_question_pattern . ' string'
+endif
+let shell_pattern_end='\([^\\]$\|^$\)'
+
 " The syntax of each line in a preseed file follows:
 " <owner> <question name> <question type> <value>
 " Lets sloppily refer to them as columns.
@@ -34,38 +45,47 @@ endif
 syntax cluster preseedSecond contains=preseedQuestion,preseedOwnerLC
 syntax cluster preseedThird contains=preseedBooleanType,preseedStrLikeType,preseedMultiSelType,preseedNote,preseedSelectType,preseedQuestionLC
 
+" Highlight shell syntax for include_command and friends. This is not fully
+" correct for multi-line arguments, as line continuations are flattened prior
+" to the argument being given to the shell as one single line. Reusing sh.vim
+" gets close enough to be useful though. Any patches with improvements are
+" welcome.
+syntax include @Sh syntax/sh.vim
 
 " Define the highlighting. Doesn't map perfectly to the group's intents, but
 " arguably close enough?
 
 " First column, <owner>
-hi! def link preseedOwner        Label
+hi! def link preseedOwner         Label
+hi! def link preseedShellOwner    Label
 
 " Second column, <question name>
-hi! def link preseedQuestion     Identifier
+hi! def link preseedQuestion      Identifier
+hi! def link preseedShellQuestion Special
+hi! def link preseedShellStr      Type
 
 " Third column, <question type>
-hi! def link preseedBooleanType  Type
-hi! def link preseedMultiSelType Type
-hi! def link preseedNote         Type
-hi! def link preseedSelectType   Type
-hi! def link preseedStrLikeType  Type
+hi! def link preseedBooleanType   Type
+hi! def link preseedMultiSelType  Type
+hi! def link preseedNote          Type
+hi! def link preseedSelectType    Type
+hi! def link preseedStrLikeType   Type
 
 " Fourth column, <value>
-hi! def link preseedBooleanVal   Special
-hi! def link preseedMultiSelVal  Special
-hi! def link preseedStrLikeVal   String
-hi! def link preseedVal          String
-hi! def link preseedSelectVal    Special
-hi! def link preseedMultiSelSep  Operator
-hi! def link preseedComment      Comment
+hi! def link preseedBooleanVal    Special
+hi! def link preseedMultiSelVal   Special
+hi! def link preseedStrLikeVal    String
+hi! def link preseedVal           String
+hi! def link preseedSelectVal     Special
+hi! def link preseedMultiSelSep   Operator
+hi! def link preseedComment       Comment
 
 " Line Continuation
-hi! def link preseedOwnerLC      Operator
-hi! def link preseedQuestionLC   Operator
-hi! def link preseedBooleanLC    Operator
-hi! def link preseedMultiSelLC   Operator
-hi! def link preseedStrLikeLC    Operator
+hi! def link preseedOwnerLC       Operator
+hi! def link preseedQuestionLC    Operator
+hi! def link preseedBooleanLC     Operator
+hi! def link preseedMultiSelLC    Operator
+hi! def link preseedStrLikeLC     Operator
 
 
 " Add the syntax matching rules.
@@ -95,7 +115,7 @@ sy match preseedStrLikeVal contained /.*/me=e
 sy match preseedStrLikeVal contained /.*\\/me=e-1 nextgroup=preseedStrLikeLC
 
 
-" Line continuation needs to be down here override everything other syntax.
+" Line continuation needs to be down here override other syntax.
 sy match preseedBooleanLC contained /\s*\\$/ nextgroup=preseedBooleanVal,preseedBooleanLC skipnl
 sy match preseedMultiSelLC contained /\\$/ nextgroup=preseedMultiSelVal skipnl
 sy match preseedOwnerLC contained /\s*\\$/ nextgroup=@preseedSecond skipnl
@@ -103,5 +123,12 @@ sy match preseedQuestionLC contained /\s*\\$/ nextgroup=@preseedThird skipnl
 sy match preseedSelectLC contained /\s*\\$/ nextgroup=preseedSelectVal,preseedSelectLC skipnl
 sy match preseedStrLikeLC contained /\\$/ nextgroup=preseedStrLikeVal skipnl
 
+" Argument to some questions is embedded shell script code.
+execute 'syn region preseedShell start="' . shell_pattern_start . '"' . ' end="' . shell_pattern_end . '" contains=preseedShellOwner,@Sh'
+syn region notShell start="whatever" end='\([^\x5c]\$\|^$\)' contains=preseedShellOwner,@Sh
+sy match preseedShellOwner contained /^\s*[[:alnum:]._-]\+\(\s\|$\)/ nextgroup=preseedShellQuestion
+sy match preseedShellQuestion contained "\s*\([[:alnum:]._-]\+/\)\+[[:alnum:]._-]\+\(\s\|$\)" nextgroup=preseedShellStr
+sy match preseedShellStr contained /string/
+
 " And comments must override everything else.
 sy match preseedComment /^\s*#.*/