All tests passing for C implementation.

packages/c/.gitignore

@@ -0,0 +1 @@
+test/test-runner

packages/c/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "@terrace/c",
+  "version": "0.0.1",
+  "license": "MIT",
+  "scripts": {
+    "build:test": "cc ./test/test-runner.c -o test/test-runner",
+    "test": "./test/test-runner"
+  }
+}

packages/c/parser.h

@@ -2,6 +2,7 @@
 #define TERRACE_PARSER_H
 
 struct terrace_linedata_s {
+  char indent;
   unsigned int level;
   unsigned int offsetHead;
   unsigned int offsetTail;
@@ -10,13 +11,13 @@ struct terrace_linedata_s {
 typedef struct terrace_linedata_s terrace_linedata_t;
 
 void terrace_parse_line(char* line, terrace_linedata_t *lineData) {
-  if (line[0] == '\n') {
+  if (line == 0) {
     // Reuse lineData->level from previous line.
     lineData->offsetHead = 0;
     lineData->offsetTail = 0;
   } else {
     unsigned int level = 0;
-    while (line[level] == ' ' && level <= lineData->level + 1) ++level;
+    while (line[level] == lineData->indent && level <= lineData->level + 1) ++level;
     lineData->level = level;
     lineData->offsetHead = level;
     lineData->offsetTail = level;

packages/c/test/test-runner.c

@@ -0,0 +1,63 @@
+#include "../parser.h"
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+
+void linedata_basic (char indent) {
+  char *line = NULL;
+  size_t bufsize = 32;
+  ssize_t c_read = 0;
+
+  terrace_linedata_t line_data;
+  line_data.indent = indent;
+
+  while(c_read = getline(&line, &bufsize, stdin)) {
+    if (c_read == -1) break;
+    char *terrace_line = strtok(line, "\n");
+    terrace_parse_line(terrace_line, &line_data);
+    if (terrace_line == 0) terrace_line = "";
+
+    printf("| level %u | indent %c | offsetHead %u | offsetTail %u | line %s |\n", line_data.level, line_data.indent, line_data.offsetHead, line_data.offsetTail, terrace_line);
+  };
+}
+
+void linedata_head_tail (char indent) {
+  char *line = NULL;
+  size_t bufsize = 32;
+  ssize_t c_read = 0;
+
+  terrace_linedata_t line_data;
+  line_data.indent = indent;
+
+  char *head;
+  char *tail;
+
+  while(c_read = getline(&line, &bufsize, stdin)) {
+    if (c_read == -1) break;
+    char *terrace_line = strtok(line, "\n");
+    terrace_parse_line(terrace_line, &line_data);
+    if (terrace_line == 0) terrace_line = "";
+
+    if (line_data.offsetTail < c_read) tail = &terrace_line[line_data.offsetTail + 1];
+    else tail = "";
+
+    // Cheeky move to avoid string slicing.
+    if (line_data.offsetHead < c_read) {
+      terrace_line[line_data.offsetTail] = '\0';
+      head = &terrace_line[line_data.offsetHead];
+    }
+    else head = "";
+
+    printf("| head %s | tail %s |\n", head, tail);
+  };
+}
+
+int main(int argc, char *argv[]) {
+  if (argc < 2) return 0;
+
+  char* test = argv[1];
+  if (!strcmp(test, "linedata:basic")) linedata_basic(' ');
+  if (!strcmp(test, "linedata:tabs")) linedata_basic('\t');
+  if (!strcmp(test, "linedata:head-tail")) linedata_head_tail(' ');
+  return 0;
+}