term: move the term core to subprojects/term

The core now builds, tests, and benchmarks alone, as a Meson subproject
with no dependency on the main tree.

- include/term/ holds term.h and the header-only unicode/. src/ holds
  the core and its private headers. The main tree gets only
  include/term through term_dep, so it cannot reach a private header.
- The term tests, the term benchmarks, the Kitty parser suite, and
  tools/amalgamate.py and tools/generate_unicode.py move with it. The
  tests run as term:<name>.
- The main build passes its -march (arch_flag) and b_ndebug to the
  subproject. A directory configured before this commit needs
  meson configure -Dterm:arch_flag=-march=... once.
- The term tests compile with -UNDEBUG. They do work inside assert.
- The subproject exports term_test_dep with term_api.h, for the main
  tree's render, thumbnail, color, and selection tests.
- The Kitty bridge used struct vector2i and has not compiled since the
  public API redesign. It builds again. 2 of its 14 tests fail: REP
  after a tab, and a cursor report after a resize.
- dirgraph.py drops the term and unicode layers. Its self-test uses pty.
- The symbols test ignores the __odr_asan symbols that ASan adds.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 94 insertions, 0 deletions

diff --git a/tools/amalgamate.py b/tools/amalgamate.py
new file mode 100644
index 0000000..f2cdf3b
--- /dev/null
+++ b/tools/amalgamate.py
@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+"""Write the term core as one term.c and one term.h.
+
+term.h joins the public headers. term.c joins every source file and puts
+each private header in at its first include. A host compiles term.c once,
+with any C11 compiler, and links libm.
+
+    amalgamate.py TERM_DIR OUT_DIR [DEPFILE]
+
+TERM_DIR is the directory with src/ and include/. DEPFILE lists every file
+read, for the build system.
+"""
+
+import re
+import sys
+from pathlib import Path
+
+INCLUDE = re.compile(r'^\s*#\s*include\s+"([^"]+)"')
+PUBLIC = ("term_types.h", "term_input.h", "term.h")
+
+
+class Joiner:
+    def __init__(self, root: Path):
+        self.root = root
+        # The sources find the public headers without the term/ prefix.
+        self.search = (root / "src", root / "include" / "term")
+        self.seen: set[Path] = set()
+
+    def resolve(self, name: str, base: Path) -> Path:
+        for d in (base,) + self.search:
+            p = (d / name).resolve()
+            if p.is_file():
+                return p
+        raise SystemExit(f"{base}: cannot find {name}")
+
+    def emit(self, path: Path, out: list[str]) -> None:
+        """Copy path to out. Replace each local include with the file,
+        the first time only."""
+        self.seen.add(path)
+        rel = path.relative_to(self.root)
+        out.append(f"/* ---- {rel} ---- */\n")
+        for line in path.read_text().splitlines(keepends=True):
+            m = INCLUDE.match(line)
+            if not m:
+                out.append(line)
+                continue
+            dep = self.resolve(m.group(1), path.parent)
+            if dep not in self.seen:
+                self.emit(dep, out)
+        out.append(f"/* ---- end {rel} ---- */\n")
+
+
+def sources(src: Path) -> list[Path]:
+    files = sorted(src.glob("*.c")) + sorted((src / "osc").glob("*.c"))
+    return [f.resolve() for f in files]
+
+
+def main() -> int:
+    if len(sys.argv) not in (3, 4):
+        print(__doc__, file=sys.stderr)
+        return 2
+    root = Path(sys.argv[1]).resolve()
+    public = root / "include" / "term"
+    out_dir = Path(sys.argv[2])
+    out_dir.mkdir(parents=True, exist_ok=True)
+    banner = "/* Generated by tools/amalgamate.py. Do not edit. */\n"
+
+    header = Joiner(root)
+    text = [banner]
+    header.emit(public / "term.h", text)
+    (out_dir / "term.h").write_text("".join(text))
+
+    body = Joiner(root)
+    text = [banner,
+            "/* The private headers have helpers that only some platforms or\n"
+            " * callers outside the core use. Clang warns about them here. */\n"
+            "#if defined(__clang__)\n"
+            '#pragma clang diagnostic ignored "-Wunused-function"\n'
+            "#endif\n",
+            '#include "term.h"\n']
+    # The public headers are in term.h, so the sources skip them.
+    body.seen.update((public / name).resolve() for name in PUBLIC)
+    for src in sources(root / "src"):
+        body.emit(src, text)
+    (out_dir / "term.c").write_text("".join(text))
+    if len(sys.argv) == 4:
+        read = sorted(header.seen | body.seen)
+        deps = " ".join(str(p).replace(" ", "\\ ") for p in read)
+        Path(sys.argv[3]).write_text(f"{out_dir / 'term.c'}: {deps}\n")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())