From 0bba8e8d7d3bf251743e8e1edb000ebb164e3699 Mon Sep 17 00:00:00 2001 From: "Scott L. Burson" Date: Sun, 11 Jan 2026 01:04:25 -0800 Subject: [PATCH] userdiff: extend Scheme support to cover other Lisp dialects Common Lisp has top-level forms, such as 'defun' and 'defmacro', that are not matched by the current Scheme pattern. Also, it is more common in CL, when defining user macros intended as top-level forms, to prefix their names with "def" instead of "define"; such forms are also not matched. And some top-level forms don't even begin with "def". On the other hand, it is an established formatting convention in the Lisp community that only top-level forms start at the left margin. So matching any unindented line starting with an open parenthesis is an acceptable heuristic; false positives will be rare. However, there are also cases where notionally top-level forms are grouped together within some containing form. At least in the Common Lisp community, it is conventional to indent these by two spaces, or sometimes one. But matching just an open parenthesis indented by two spaces would be too broad; so the pattern added by this commit requires an indented form to start with "(def". It is believed that this strikes a good balance between potential false positives and false negatives. Signed-off-by: Scott L. Burson --- Documentation/gitattributes.adoc | 1 + t/t4018/scheme-lisp-defun-a | 4 ++++ t/t4018/scheme-lisp-defun-b | 4 ++++ t/t4018/scheme-lisp-eval-when | 4 ++++ t/t4018/{scheme-module => scheme-module-a} | 0 t/t4018/scheme-module-b | 6 ++++++ userdiff.c | 22 ++++++++++++++++------ 7 files changed, 35 insertions(+), 6 deletions(-) create mode 100644 t/t4018/scheme-lisp-defun-a create mode 100644 t/t4018/scheme-lisp-defun-b create mode 100644 t/t4018/scheme-lisp-eval-when rename t/t4018/{scheme-module => scheme-module-a} (100%) create mode 100644 t/t4018/scheme-module-b diff --git a/Documentation/gitattributes.adoc b/Documentation/gitattributes.adoc index f20041a323d174..705162f22aeaa5 100644 --- a/Documentation/gitattributes.adoc +++ b/Documentation/gitattributes.adoc @@ -912,6 +912,7 @@ patterns are available: - `rust` suitable for source code in the Rust language. - `scheme` suitable for source code in the Scheme language. +Also handles Emacs Lisp, Common Lisp, and other dialects. - `tex` suitable for source code for LaTeX documents. diff --git a/t/t4018/scheme-lisp-defun-a b/t/t4018/scheme-lisp-defun-a new file mode 100644 index 00000000000000..c3c750f76d7b07 --- /dev/null +++ b/t/t4018/scheme-lisp-defun-a @@ -0,0 +1,4 @@ +(defun some-func (x y z) RIGHT + (let ((a x) + (b y)) + (ChangeMe a b))) diff --git a/t/t4018/scheme-lisp-defun-b b/t/t4018/scheme-lisp-defun-b new file mode 100644 index 00000000000000..21be305968bf6b --- /dev/null +++ b/t/t4018/scheme-lisp-defun-b @@ -0,0 +1,4 @@ +(macrolet ((foo (x) `(bar ,x))) + (defun mumble (x) ; RIGHT + (when (> x 0) + (foo x)))) ; ChangeMe diff --git a/t/t4018/scheme-lisp-eval-when b/t/t4018/scheme-lisp-eval-when new file mode 100644 index 00000000000000..5d941d7e0edda2 --- /dev/null +++ b/t/t4018/scheme-lisp-eval-when @@ -0,0 +1,4 @@ +(eval-when (:compile-toplevel :load-toplevel :execute) ; RIGHT + (set-macro-character #\? + (lambda (stream char) + `(make-pattern-variable ,(read stream))))) ; ChangeMe diff --git a/t/t4018/scheme-module b/t/t4018/scheme-module-a similarity index 100% rename from t/t4018/scheme-module rename to t/t4018/scheme-module-a diff --git a/t/t4018/scheme-module-b b/t/t4018/scheme-module-b new file mode 100644 index 00000000000000..77bc0c5eff4775 --- /dev/null +++ b/t/t4018/scheme-module-b @@ -0,0 +1,6 @@ +(module A + (export with-display-exception) + (extern (display-exception display-exception)) + (def (with-display-exception thunk) RIGHT + (with-catch (lambda (e) (display-exception e (current-error-port)) e) + thunk ChangeMe))) diff --git a/userdiff.c b/userdiff.c index fe710a68bfdfa6..561ef9cdcea6d5 100644 --- a/userdiff.c +++ b/userdiff.c @@ -344,14 +344,24 @@ PATTERNS("rust", "|[0-9][0-9_a-fA-Fiosuxz]*(\\.([0-9]*[eE][+-]?)?[0-9_fF]*)?" "|[-+*\\/<>%&^|=!:]=|<<=?|>>=?|&&|\\|\\||->|=>|\\.{2}=|\\.{3}|::"), PATTERNS("scheme", - "^[\t ]*(\\(((define|def(struct|syntax|class|method|rules|record|proto|alias)?)[-*/ \t]|(library|module|struct|class)[*+ \t]).*)$", /* - * R7RS valid identifiers include any sequence enclosed - * within vertical lines having no backslashes + * An unindented opening parenthesis identifies a top-level + * expression in all Lisp dialects. */ - "\\|([^\\\\]*)\\|" - /* All other words should be delimited by spaces or parentheses */ - "|([^][)(}{[ \t])+"), + "^(\\(.*)$\n" + /* For Scheme: a possibly indented left paren followed by a keyword. */ + "^[\t ]*(\\(((define|def(struct|syntax|class|method|rules|record|proto|alias)?)[-*/ \t]|(library|module|struct|class)[*+ \t]).*)$\n" + /* + * For all Lisp dialects: a slightly indented line starting with "(def". + */ + "^ {1,2}(\\([Dd][Ee][Ff].*)$", + /* + * The union of R7RS and Common Lisp symbol syntax: allows arbitrary + * strings between vertical bars, including any escaped characters. + */ + "\\|([^\\\\]|\\\\.)*\\|" + /* All other words should be delimited by spaces or parentheses. */ + "|([^][)(}{ \t])+"), PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$", "\\\\[a-zA-Z@]+|\\\\.|([a-zA-Z0-9]|[^\x01-\x7f])+"), { .name = "default", .binary = -1 },