From b33112a43e500eb6e07fe3214c18de75a9234ca8 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 12:51:15 +1000
Subject: [PATCH 1/7] Disable bnfc --tree-sitter by default

If needed and you have bnfc-treesitter fork installed,
you can re-generate the tree-sitter grammar.js with:

    BINCAML_BNFC_TREESITTER=true dune runtest tree-sitter --auto-promote

I should also add the bnfc-treesitter fork to the nix devshell,
but i'll avoid doing that for now because it would conflict with
the revert PR.
---
 tree-sitter/dune | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tree-sitter/dune b/tree-sitter/dune
index ca13dd0c..dc2376e7 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -10,10 +10,13 @@
 ; check that grammar.js is up to date.
 ; requires `bnfc-treesitter` from pac-nix.
 
+; bnfc tree-sitter backend is only run if BINCAML_BNFC_TREESITTER
+; is set to true, and it is false by default. this lets us use
+; upstream bnfc for the main ocaml generation.
 (rule
  (alias runtest)
  (deps %{project_root}/lib/fe/BasilIR.cf)
- (enabled_if %{bin-available:bnfc})
+ (enabled_if %{env:BINCAML_BNFC_TREESITTER=false})
  (action
   (progn
    (copy %{deps} basilir.cf)

From ea6f12bbc58347cc32c8a91f9280f9c27f829e8c Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 13:08:05 +1000
Subject: [PATCH 2/7] fm

---
 tree-sitter/dune | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tree-sitter/dune b/tree-sitter/dune
index dc2376e7..d61ef069 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -13,6 +13,7 @@
 ; bnfc tree-sitter backend is only run if BINCAML_BNFC_TREESITTER
 ; is set to true, and it is false by default. this lets us use
 ; upstream bnfc for the main ocaml generation.
+
 (rule
  (alias runtest)
  (deps %{project_root}/lib/fe/BasilIR.cf)

From aa4b7fec73d01b912ebd69b6cfccafb6044ee921 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 13:41:22 +1000
Subject: [PATCH 3/7] do clever things with detecting --tree-sitter

---
 lib/fe/dune            |  6 ++++++
 tree-sitter/.gitignore |  2 ++
 tree-sitter/dune       | 12 ++++++++++--
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/lib/fe/dune b/lib/fe/dune
index 9771b1ac..bbbf26ad 100644
--- a/lib/fe/dune
+++ b/lib/fe/dune
@@ -45,3 +45,9 @@
  (flags
   (:standard -open BasilIR))
  (libraries bincaml.basilir))
+
+(rule
+ (deps (universe))
+ (action
+  (with-stdout-to tree-sitter-available
+   (bash "if bnfc --help | grep -q -- --tree-sitter; then printf true; else printf false; fi"))))
diff --git a/tree-sitter/.gitignore b/tree-sitter/.gitignore
index b73cc51b..869c50dd 100644
--- a/tree-sitter/.gitignore
+++ b/tree-sitter/.gitignore
@@ -1,3 +1,5 @@
+grammar.js.new
+
 # Rust artifacts
 target/
 
diff --git a/tree-sitter/dune b/tree-sitter/dune
index d61ef069..f5fc3da7 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -13,11 +13,10 @@
 ; bnfc tree-sitter backend is only run if BINCAML_BNFC_TREESITTER
 ; is set to true, and it is false by default. this lets us use
 ; upstream bnfc for the main ocaml generation.
-
 (rule
  (alias runtest)
  (deps %{project_root}/lib/fe/BasilIR.cf)
- (enabled_if %{env:BINCAML_BNFC_TREESITTER=false})
+ (enabled_if %{read:../lib/fe/tree-sitter-available})
  (action
   (progn
    (copy %{deps} basilir.cf)
@@ -29,3 +28,12 @@
     basilir.cf
     --makefile)
    (diff? grammar.js tree-sitter-basilir/grammar.js))))
+
+(rule
+ (alias runtest)
+ (deps (universe))
+ (enabled_if (not %{read:../lib/fe/tree-sitter-available}))
+ (action
+  (echo
+    "tree-sitter/dune: bnfc tree-sitter generation skipped,"
+    "because the installed bnfc doesn't support it.\n")))

From 788b97e811e4a2e6a7ce90b2f885bb3f6779f309 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 13:51:10 +1000
Subject: [PATCH 4/7] very clever

---
 lib/fe/dune      | 15 ++++++++++++---
 tree-sitter/dune | 10 +++++-----
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/lib/fe/dune b/lib/fe/dune
index bbbf26ad..2e03264f 100644
--- a/lib/fe/dune
+++ b/lib/fe/dune
@@ -47,7 +47,16 @@
  (libraries bincaml.basilir))
 
 (rule
- (deps (universe))
+ (target has-bnfc-tree-sitter)
+ (enabled_if (not %{bin-available:bnfc}))
+ (action (with-stdout-to %{target} (echo "false"))))
+
+(rule
+ (target has-bnfc-tree-sitter)
+ (enabled_if %{bin-available:bnfc})
+ (deps %{bin:bnfc})
  (action
-  (with-stdout-to tree-sitter-available
-   (bash "if bnfc --help | grep -q -- --tree-sitter; then printf true; else printf false; fi"))))
+  (with-stdout-to %{target}
+   (bash "bnfc --help | { if grep -q -- --tree-sitter; then printf true; else printf false; fi }"))))
+; bash pipe structure is so that if `bnfc` exits with an error, we report that error and fail.
+; "false" is only written if bnfc succeeds but tree-sitter was not found.
diff --git a/tree-sitter/dune b/tree-sitter/dune
index f5fc3da7..80e1e885 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -10,13 +10,13 @@
 ; check that grammar.js is up to date.
 ; requires `bnfc-treesitter` from pac-nix.
 
-; bnfc tree-sitter backend is only run if BINCAML_BNFC_TREESITTER
-; is set to true, and it is false by default. this lets us use
-; upstream bnfc for the main ocaml generation.
+; bnfc tree-sitter backend is only run if tree-sitter is detected
+; in the output of bnfc --help. this lets us use upstream bnfc
+; for the main ocaml generation.
 (rule
  (alias runtest)
  (deps %{project_root}/lib/fe/BasilIR.cf)
- (enabled_if %{read:../lib/fe/tree-sitter-available})
+ (enabled_if %{read:../lib/fe/has-bnfc-tree-sitter})
  (action
   (progn
    (copy %{deps} basilir.cf)
@@ -32,7 +32,7 @@
 (rule
  (alias runtest)
  (deps (universe))
- (enabled_if (not %{read:../lib/fe/tree-sitter-available}))
+ (enabled_if (not %{read:../lib/fe/has-bnfc-tree-sitter}))
  (action
   (echo
     "tree-sitter/dune: bnfc tree-sitter generation skipped,"

From 5987da9f2d0fea81e49567ef2bf4c7ab54e3c890 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 13:57:14 +1000
Subject: [PATCH 5/7] fmt

---
 lib/fe/dune      | 15 +++++++++++----
 tree-sitter/dune |  8 +++++---
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/lib/fe/dune b/lib/fe/dune
index 2e03264f..ab7ac3dc 100644
--- a/lib/fe/dune
+++ b/lib/fe/dune
@@ -48,15 +48,22 @@
 
 (rule
  (target has-bnfc-tree-sitter)
- (enabled_if (not %{bin-available:bnfc}))
- (action (with-stdout-to %{target} (echo "false"))))
+ (enabled_if
+  (not %{bin-available:bnfc}))
+ (action
+  (with-stdout-to
+   %{target}
+   (echo "false"))))
 
 (rule
  (target has-bnfc-tree-sitter)
  (enabled_if %{bin-available:bnfc})
  (deps %{bin:bnfc})
  (action
-  (with-stdout-to %{target}
-   (bash "bnfc --help | { if grep -q -- --tree-sitter; then printf true; else printf false; fi }"))))
+  (with-stdout-to
+   %{target}
+   (bash
+    "bnfc --help | { if grep -q -- --tree-sitter; then printf true; else printf false; fi }"))))
+
 ; bash pipe structure is so that if `bnfc` exits with an error, we report that error and fail.
 ; "false" is only written if bnfc succeeds but tree-sitter was not found.
diff --git a/tree-sitter/dune b/tree-sitter/dune
index 80e1e885..0c0fdcf6 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -13,6 +13,7 @@
 ; bnfc tree-sitter backend is only run if tree-sitter is detected
 ; in the output of bnfc --help. this lets us use upstream bnfc
 ; for the main ocaml generation.
+
 (rule
  (alias runtest)
  (deps %{project_root}/lib/fe/BasilIR.cf)
@@ -32,8 +33,9 @@
 (rule
  (alias runtest)
  (deps (universe))
- (enabled_if (not %{read:../lib/fe/has-bnfc-tree-sitter}))
+ (enabled_if
+  (not %{read:../lib/fe/has-bnfc-tree-sitter}))
  (action
   (echo
-    "tree-sitter/dune: bnfc tree-sitter generation skipped,"
-    "because the installed bnfc doesn't support it.\n")))
+   "tree-sitter/dune: bnfc tree-sitter generation skipped,"
+   "because the installed bnfc doesn't support it.\n")))

From e5c05864a7bf372b85217b3a976c8f0361f02556 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 14:05:56 +1000
Subject: [PATCH 6/7] use dune pipeline

---
 lib/fe/dune | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/fe/dune b/lib/fe/dune
index ab7ac3dc..f79cb8a6 100644
--- a/lib/fe/dune
+++ b/lib/fe/dune
@@ -58,12 +58,13 @@
 (rule
  (target has-bnfc-tree-sitter)
  (enabled_if %{bin-available:bnfc})
- (deps %{bin:bnfc})
  (action
   (with-stdout-to
    %{target}
-   (bash
-    "bnfc --help | { if grep -q -- --tree-sitter; then printf true; else printf false; fi }"))))
+   (pipe-stdout
+    (run bnfc --help)
+    (bash
+     "if grep -q -- --tree-sitter; then printf true; else printf false; fi")))))
 
-; bash pipe structure is so that if `bnfc` exits with an error, we report that error and fail.
+; if `bnfc` exits with an error, we report that error and fail.
 ; "false" is only written if bnfc succeeds but tree-sitter was not found.

From ad922b8bb1ec4020cbc9e81dfd2acb582978e353 Mon Sep 17 00:00:00 2001
From: rina <k@rina.fyi>
Date: Mon, 9 Mar 2026 14:10:39 +1000
Subject: [PATCH 7/7] we actually need to detect the specific tree-sitter fork

---
 lib/fe/dune      | 2 +-
 tree-sitter/dune | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/fe/dune b/lib/fe/dune
index f79cb8a6..ad596b62 100644
--- a/lib/fe/dune
+++ b/lib/fe/dune
@@ -64,7 +64,7 @@
    (pipe-stdout
     (run bnfc --help)
     (bash
-     "if grep -q -- --tree-sitter; then printf true; else printf false; fi")))))
+     "if grep -q -- --tree-sitter-word; then printf true; else printf false; fi")))))
 
 ; if `bnfc` exits with an error, we report that error and fail.
 ; "false" is only written if bnfc succeeds but tree-sitter was not found.
diff --git a/tree-sitter/dune b/tree-sitter/dune
index 0c0fdcf6..e7ee71c3 100644
--- a/tree-sitter/dune
+++ b/tree-sitter/dune
@@ -10,9 +10,9 @@
 ; check that grammar.js is up to date.
 ; requires `bnfc-treesitter` from pac-nix.
 
-; bnfc tree-sitter backend is only run if tree-sitter is detected
-; in the output of bnfc --help. this lets us use upstream bnfc
-; for the main ocaml generation.
+; bnfc tree-sitter backend is only run if the fixed tree-sitter fork is
+; detected in the output of bnfc --help. this lets us use upstream
+; bnfc for the main ocaml parser.
 
 (rule
  (alias runtest)