Hermit/tests/test_skills.c

/* Skills: frontmatter, discovery order, prompt index, the skill tool and
 * path containment. */
#define _POSIX_C_SOURCE 200809L

#include "cst_agent.h"
#include "cst_skills.h"
#include "cst_tools.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include "cst_test_util.h"

static int nfail;

#define CHECK(cond, msg)                                                       \
  do {                                                                         \
    if (!(cond)) {                                                             \
      fprintf(stderr, "FAIL %s:%d: %s\n", __FILE__, __LINE__, msg);            \
      nfail++;                                                                 \
    }                                                                          \
  } while (0)

static char g_root[256];

static void put(const char *rel, const char *text) {
  char p[512];
  snprintf(p, sizeof(p), "%s/%s", g_root, rel);
  for (char *q = p + strlen(g_root) + 1; *q; q++) {
    if (*q == '/') {
      *q = 0;
      test_mkdir(p, 0755);
      *q = '/';
    }
  }
  FILE *fp = fopen(p, "wb");
  if (fp) {
    fputs(text, fp);
    fclose(fp);
  }
}

static void frontmatter(void) {
  char v[256];
  const char *t = "---\nname: \"pdf-tools\"\ndescription: >\n  Fill PDF\n  "
                  "forms.\ntools: [read_file, grep ]\nmodel: deepseek-pro\n"
                  "list:\n  - a\n  - b\nlit: |\n  one\n  two\n---\n\n# Body\n";
  CHECK(cst_fm_get(t, "name", v, sizeof(v)) && strcmp(v, "pdf-tools") == 0,
        "quoted value");
  CHECK(cst_fm_get(t, "description", v, sizeof(v)) &&
            strcmp(v, "Fill PDF forms.") == 0,
        "folded value");
  CHECK(cst_fm_get(t, "tools", v, sizeof(v)) &&
            strcmp(v, "read_file,grep") == 0,
        "flow list");
  CHECK(cst_fm_get(t, "list", v, sizeof(v)) && strcmp(v, "a,b") == 0,
        "block list");
  CHECK(cst_fm_get(t, "lit", v, sizeof(v)) && strcmp(v, "one\ntwo") == 0,
        "literal block");
  CHECK(!cst_fm_get(t, "nope", v, sizeof(v)), "missing key");
  CHECK(strcmp(cst_fm_body(t), "# Body\n") == 0, "body after fence");
  CHECK(strcmp(cst_fm_body("no frontmatter\n"), "no frontmatter\n") == 0,
        "no frontmatter: whole text");
  CHECK(!cst_fm_get("---\nname: x\n", "name", v, sizeof(v)),
        "unclosed frontmatter ignored");
}

int main(void) {
  frontmatter();

  if (test_tmpdir(g_root, sizeof(g_root), "cst-skills") != 0) {
    perror("tmpdir");
    return 1;
  }
  char ws[300], cfgdir[300];
  snprintf(ws, sizeof(ws), "%s/ws", g_root);
  snprintf(cfgdir, sizeof(cfgdir), "%s/cfg", g_root);
  setenv("XDG_CONFIG_HOME", cfgdir, 1);

  put("ws/.agent/skills/zeta/SKILL.md",
      "---\nname: zeta\ndescription: Last one alphabetically.\n---\nDo Z.\n");
  put("ws/.agent/skills/forms/SKILL.md",
      "---\nname: pdf-forms\ndescription: Fill PDF forms with the bundled "
      "script.\n---\n# PDF forms\n\nRun scripts/fill.py.\n");
  put("ws/.agent/skills/forms/scripts/fill.py", "print('fill')\n");
  put("ws/.agent/skills/forms/reference.md", "Field names...\n");
  put("ws/.claude/skills/plain/SKILL.md", "# Plain\n\nA skill without "
                                          "frontmatter.\n");
  put("cfg/cst-agent/skills/forms2/SKILL.md",
      "---\nname: pdf-forms\ndescription: shadowed by the workspace\n---\n");
  put("cfg/cst-agent/skills/userskill/SKILL.md",
      "---\nname: user-skill\ndescription: From the config dir.\n---\nU\n");
  put("ws/secret.txt", "top secret\n");
  {
    char link[512], target[512];
    snprintf(link, sizeof(link), "%s/ws/.agent/skills/forms/leak", g_root);
    snprintf(target, sizeof(target), "%s/ws/secret.txt", g_root);
    if (test_symlink(target, link) != 0)
      fprintf(stderr, "note: no symlinks here, escape check is partial\n");
  }

  cst_skill_t v[CST_SKILLS_MAX];
  int n = cst_skills_list(ws, v, CST_SKILLS_MAX);
  CHECK(n == 4, "four distinct skills");
  CHECK(n == 4 && strcmp(v[0].name, "pdf-forms") == 0 &&
            strcmp(v[1].name, "plain") == 0 &&
            strcmp(v[2].name, "user-skill") == 0 &&
            strcmp(v[3].name, "zeta") == 0,
        "sorted by name");
  CHECK(n == 4 && strcmp(v[0].source, "workspace") == 0 &&
            strstr(v[0].desc, "bundled script"),
        "workspace wins over the config dir");
  CHECK(n == 4 && strcmp(v[1].source, "claude") == 0 &&
            strcmp(v[1].desc, "A skill without frontmatter.") == 0,
        ".claude skill, description from the body");

  char *ix = cst_skills_index(ws);
  CHECK(ix && strstr(ix, "- pdf-forms: Fill PDF forms") &&
            strstr(ix, "- zeta: Last one"),
        "index lists name: description");
  free(ix);

  int code = -1;
  char *out = cst_skill_read(ws, "pdf-forms", NULL, &code);
  CHECK(code == 0 && out && strstr(out, "# PDF forms\n\nRun scripts/fill.py.") &&
            !strstr(out, "description:"),
        "SKILL.md body without frontmatter");
  CHECK(out && strstr(out, "- reference.md\n") &&
            strstr(out, "- scripts/fill.py\n"),
        "file list");
  free(out);
  out = cst_skill_read(ws, "pdf-forms", "scripts/fill.py", &code);
  CHECK(code == 0 && out && strstr(out, "print('fill')"), "read a skill file");
  free(out);
  out = cst_skill_read(ws, "pdf-forms", "../../../secret.txt", &code);
  CHECK(code == 1 && out && !strstr(out, "top secret"), "no ../ escape");
  free(out);
  out = cst_skill_read(ws, "pdf-forms", "leak", &code);
  CHECK(code == 1 && out && !strstr(out, "top secret"), "no symlink escape");
  free(out);
  out = cst_skill_read(ws, "missing", NULL, &code);
  CHECK(code == 1 && out && strstr(out, "available: pdf-forms, plain"),
        "unknown skill lists names");
  free(out);

  char *pr = cst_skill_prompt(ws, "zeta", "do the thing");
  CHECK(pr && strstr(pr, "<skill>") && strstr(pr, "Do Z.") &&
            strstr(pr, "do the thing"),
        "/skill prompt inlines the instructions");
  free(pr);

  /* tool + system prompt */
  CHECK(cst_skills_register_tool() == 0 && cst_tool_find("skill"),
        "skill tool registered");
  cst_agent_config_t cfg;
  memset(&cfg, 0, sizeof(cfg));
  snprintf(cfg.workspace_root, sizeof(cfg.workspace_root), "%s", ws);
  ctl_tool_call_t c;
  memset(&c, 0, sizeof(c));
  snprintf(c.name, sizeof(c.name), "skill");
  c.nargs = 1;
  snprintf(c.args[0].key, sizeof(c.args[0].key), "name");
  c.args[0].value = "user-skill";
  c.args[0].value_len = strlen(c.args[0].value);
  cst_tool_ctx_t ctx;
  memset(&ctx, 0, sizeof(ctx));
  ctx.workspace_root = ws;
  cst_tool_result_t r;
  memset(&r, 0, sizeof(r));
  cst_tool_run(&ctx, &c, &r);
  CHECK(r.exit_code == 0 && r.out && strstr(r.out, "skill user-skill (user)"),
        "skill tool runs");
  cst_tool_result_free(&r);
  char *sp = cst_agent_build_prompt(&cfg, CST_PROTO_NATIVE_EOS, NULL);
  CHECK(sp && strstr(sp, "Skills (call skill(name)") &&
            strstr(sp, "- user-skill: From the config dir."),
        "system prompt carries the index");
  free(sp);
  cfg.tool_profile = CST_TOOLS_MINIMAL;
  sp = cst_agent_build_prompt(&cfg, CST_PROTO_NATIVE_EOS, NULL);
  CHECK(sp && !strstr(sp, "Skills ("), "minimal prompt unchanged");
  free(sp);

  if (test_rmrf(g_root) != 0)
    fprintf(stderr, "note: cleanup failed\n");
  if (nfail) {
    fprintf(stderr, "test_skills: %d failure(s)\n", nfail);
    return 1;
  }
  printf("test_skills: OK\n");
  return 0;
}