docs: Enable Syntax Highlighting for Code Snippits

HACKING.md

@@ -11,16 +11,18 @@ The `main` highlighter
 
 The following function `pz` is useful when working on the `main` highlighting:
 
-    pq() {
-      (( $#argv )) || return 0
-      print -r -l -- ${(qqqq)argv}
-    }
-    pz() {
-      local arg
-      for arg; do
-        pq ${(z)arg}
-      done
-    }
+```zsh
+pq() {
+  (( $#argv )) || return 0
+  print -r -l -- ${(qqqq)argv}
+}
+pz() {
+  local arg
+  for arg; do
+    pq ${(z)arg}
+  done
+}
+```
 
 It prints, for each argument, its token breakdown, similar to how the main
 loop of the `main` highlighter sees it.
@@ -32,17 +34,19 @@ Since the test harness empties `ZSH_HIGHLIGHT_STYLES` and the `brackets`
 highlighter interrogates `ZSH_HIGHLIGHT_STYLES` to determine how to highlight,
 tests must set the `bracket-level-#` keys themselves.  For example:
 
-    ZSH_HIGHLIGHT_STYLES[bracket-level-1]=
-    ZSH_HIGHLIGHT_STYLES[bracket-level-2]=
+```zsh
+ZSH_HIGHLIGHT_STYLES[bracket-level-1]=
+ZSH_HIGHLIGHT_STYLES[bracket-level-2]=
 
-    BUFFER='echo ({x})'
+BUFFER='echo ({x})'
 
-    expected_region_highlight=(
-      "6  6  bracket-level-1" # (
-      "7  7  bracket-level-2" # {
-      "9  9  bracket-level-2" # }
-      "10 10 bracket-level-1" # )
-    )
+expected_region_highlight=(
+  "6  6  bracket-level-1" # (
+  "7  7  bracket-level-2" # {
+  "9  9  bracket-level-2" # }
+  "10 10 bracket-level-1" # )
+)
+```
 
 Testing the `pattern` and `regexp` highlighters
 -----------------------------------------------
@@ -53,20 +57,24 @@ cannot get the `ZSH_HIGHLIGHT_STYLES` keys.  Therefore, when writing tests, use
 the style itself as third word (cf. the
 [documentation for `expected_region_highlight`](docs/highlighters.md)).  For example:
 
-    ZSH_HIGHLIGHT_PATTERNS+=('rm -rf *' 'fg=white,bold,bg=red')
+```zsh
+ZSH_HIGHLIGHT_PATTERNS+=('rm -rf *' 'fg=white,bold,bg=red')
 
-    BUFFER='rm -rf /'
+BUFFER='rm -rf /'
 
-    expected_region_highlight=(
-      "1 8 fg=white,bold,bg=red" # rm -rf /
-    )
+expected_region_highlight=(
+  "1 8 fg=white,bold,bg=red" # rm -rf /
+)
+```
 
 Miscellany
 ----------
 
 If you work on the driver (`zsh-syntax-highlighting.zsh`), you may find the following zstyle useful:
 
-    zstyle ':completion:*:*:*:*:globbed-files' ignored-patterns {'*/',}zsh-syntax-highlighting.plugin.zsh
+```zsh
+zstyle ':completion:*:*:*:*:globbed-files' ignored-patterns {'*/',}zsh-syntax-highlighting.plugin.zsh
+```
 
 IRC channel
 -----------