From 4bcf6565cdb9c8de0f956609da8a9998d6e2d140 Mon Sep 17 00:00:00 2001
From: Calvin Rose <calsrose@gmail.com>
Date: Thu, 31 Jan 2019 14:48:28 -0500
Subject: [PATCH] Add parser/insert and bump to 0.4.0

---
 CHANGELOG.md              |  1 +
 src/core/core.janet       |  6 ++++--
 src/core/parse.c          | 40 +++++++++++++++++++++++++++++++++++++++
 src/include/janet/janet.h |  2 +-
 4 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d58720a4..3f879249 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 All notable changes to this project will be documented in this file.
 
 ## 0.4.0 - ??
+- Add parser/insert to modify parser state programmatically
 - Add debug/stacktrace for easy, pretty stacktraces
 - Remove the status-pp function
 - Update API to run-context to be much more sane
diff --git a/src/core/core.janet b/src/core/core.janet
index 1efafff2..b4a6bcd0 100644
--- a/src/core/core.janet
+++ b/src/core/core.janet
@@ -1393,12 +1393,14 @@ value, one key will be ignored."
               where
               " around byte "
               (string (parser/where p))
-              (or (parser/error p) "unmatched delimiter")))
+              ": "
+              (or (parser/error p) "unmatched delimiter")
+              "\n"))
 
 (defn bad-compile
   "Default handler for a compile error."
   [msg macrof where]
-  (file/write stderr msg " while compiling " where "\n")
+  (file/write stderr "compile error: " msg " while compiling " where "\n")
   (when macrof (debug/stacktrace macrof)))
 
 (defn getline
diff --git a/src/core/parse.c b/src/core/parse.c
index 1dbfab56..00cad587 100644
--- a/src/core/parse.c
+++ b/src/core/parse.c
@@ -649,6 +649,39 @@ static Janet cfun_parse_consume(int32_t argc, Janet *argv) {
     return janet_wrap_integer(i);
 }
 
+static Janet cfun_parse_insert(int32_t argc, Janet *argv) {
+    janet_fixarity(argc, 2);
+    JanetParser *p = janet_getabstract(argv, 0, &janet_parse_parsertype);
+    JanetParseState *s = p->states + p->statecount - 1;
+    if (s->consumer == tokenchar) {
+        janet_parser_consume(p, ' ');
+        p->offset--;
+        s = p->states + p->statecount - 1;
+    }
+    if (s->flags & PFLAG_CONTAINER) {
+        s->argn++;
+        if (p->statecount == 1) p->pending++;
+        push_arg(p, argv[1]);
+    } else if (s->flags & (PFLAG_STRING | PFLAG_LONGSTRING)) {
+        const uint8_t *str = janet_to_string(argv[1]);
+        int32_t slen = janet_string_length(str);
+        size_t newcount = p->bufcount + slen;
+        if (p->bufcap > p->bufcount + slen) {
+            size_t newcap = 2 * newcount;
+            p->buf = realloc(p->buf, newcap);
+            if (p->buf == NULL) {
+                JANET_OUT_OF_MEMORY;
+            }
+            p->bufcap = newcap;
+        }
+        memcpy(p->buf + p->bufcount, str, slen);
+        p->bufcount = newcount;
+    } else {
+        janet_panic("cannot insert value into parser");
+    }
+    return argv[0];
+}
+
 static Janet cfun_parse_has_more(int32_t argc, Janet *argv) {
     janet_fixarity(argc, 1);
     JanetParser *p = janet_getabstract(argv, 0, &janet_parse_parsertype);
@@ -807,6 +840,13 @@ static const JanetReg parse_cfuns[] = {
                 "in the byte stream as a tuple (line, column). Lines and columns are counted from "
                 "1, (the first byte is line 1, column 1) and a newline is considered ASCII 0x0A.")
     },
+    {
+        "parser/insert", cfun_parse_insert,
+        JDOC("(parser/insert parser value)\n\n"
+                "Insert a value into the parser. This means that the parser state can be manipulated "
+                "in between chunks of bytes. This would allow a user to add extra elements to arrays "
+                "and tuples, for example. Returns the parser.")
+    },
     {NULL, NULL, NULL}
 };
 
diff --git a/src/include/janet/janet.h b/src/include/janet/janet.h
index de0d5ac5..f7785fcc 100644
--- a/src/include/janet/janet.h
+++ b/src/include/janet/janet.h
@@ -29,7 +29,7 @@ extern "C" {
 
 /***** START SECTION CONFIG *****/
 
-#define JANET_VERSION "0.3.0"
+#define JANET_VERSION "0.4.0"
 
 #ifndef JANET_BUILD
 #define JANET_BUILD "local"