scalar: implement `scalar diagnose`
Over the course of Scalar's development, it became obvious that there is a need for a command that can gather all kinds of useful information that can help identify the most typical problems with large worktrees/repositories. The `diagnose` command is the culmination of this hard-won knowledge: it gathers the installed hooks, the config, a couple statistics describing the data shape, among other pieces of information, and then wraps everything up in a tidy, neat `.zip` archive. Note: originally, Scalar was implemented in C# using the .NET API, where we had the luxury of a comprehensive standard library that includes basic functionality such as writing a `.zip` file. In the C version, we lack such a commodity. Rather than introducing a dependency on, say, libzip, we slightly abuse Git's `archive` machinery: we write out a `.zip` of the empty try, augmented by a couple files that are added via the `--add-file*` options. We are careful trying not to modify the current repository in any way lest the very circumstances that required `scalar diagnose` to be run are changed by the `diagnose` run itself. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Johannes Schindelin committed
May 28, 2022 at 16:11 UTC
aa5c79a33156c2f086ca3a149c11f1434d10f5ce
3 files changed
+170
contrib/scalar/scalar.c
+144
@@ -11,6 +11,7 @@
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#include "dir.h"
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#include "packfile.h"
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#include "help.h"
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+#include "archive.h"
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/*
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* Remove the deepest subdirectory in the provided path string. Path must not
@@ -260,6 +261,47 @@ static int unregister_dir(void)
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return res;
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}
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+static int add_directory_to_archiver(struct strvec *archiver_args,
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+ const char *path, int recurse)
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+{
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+ int at_root = !*path;
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+ DIR *dir = opendir(at_root ? "." : path);
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+ struct dirent *e;
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+ struct strbuf buf = STRBUF_INIT;
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+ size_t len;
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+ int res = 0;
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+
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+ if (!dir)
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+ return error_errno(_("could not open directory '%s'"), path);
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+
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+ if (!at_root)
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+ strbuf_addf(&buf, "%s/", path);
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+ len = buf.len;
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+ strvec_pushf(archiver_args, "--prefix=%s", buf.buf);
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+
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+ while (!res && (e = readdir(dir))) {
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+ if (!strcmp(".", e->d_name) || !strcmp("..", e->d_name))
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+ continue;
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+
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+ strbuf_setlen(&buf, len);
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+ strbuf_addstr(&buf, e->d_name);
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+
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+ if (e->d_type == DT_REG)
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+ strvec_pushf(archiver_args, "--add-file=%s", buf.buf);
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+ else if (e->d_type != DT_DIR)
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+ warning(_("skipping '%s', which is neither file nor "
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+ "directory"), buf.buf);
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+ else if (recurse &&
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+ add_directory_to_archiver(archiver_args,
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+ buf.buf, recurse) < 0)
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+ res = -1;
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+ }
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+
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+ closedir(dir);
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+ strbuf_release(&buf);
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+ return res;
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+}
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+
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/* printf-style interface, expects `<key>=<value>` argument */
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static int set_config(const char *fmt, ...)
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{
@@ -500,6 +542,107 @@ cleanup:
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return res;
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}
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+static int cmd_diagnose(int argc, const char **argv)
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+{
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+ struct option options[] = {
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+ OPT_END(),
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+ };
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+ const char * const usage[] = {
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+ N_("scalar diagnose [<enlistment>]"),
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+ NULL
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+ };
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+ struct strbuf zip_path = STRBUF_INIT;
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+ struct strvec archiver_args = STRVEC_INIT;
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+ char **argv_copy = NULL;
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+ int stdout_fd = -1, archiver_fd = -1;
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+ time_t now = time(NULL);
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+ struct tm tm;
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+ struct strbuf path = STRBUF_INIT, buf = STRBUF_INIT;
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+ int res = 0;
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+
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+ argc = parse_options(argc, argv, NULL, options,
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+ usage, 0);
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+
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+ setup_enlistment_directory(argc, argv, usage, options, &zip_path);
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+
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+ strbuf_addstr(&zip_path, "/.scalarDiagnostics/scalar_");
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+ strbuf_addftime(&zip_path,
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+ "%Y%m%d_%H%M%S", localtime_r(&now, &tm), 0, 0);
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+ strbuf_addstr(&zip_path, ".zip");
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+ switch (safe_create_leading_directories(zip_path.buf)) {
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+ case SCLD_EXISTS:
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+ case SCLD_OK:
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+ break;
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+ default:
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+ error_errno(_("could not create directory for '%s'"),
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+ zip_path.buf);
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+ goto diagnose_cleanup;
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+ }
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+ stdout_fd = dup(1);
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+ if (stdout_fd < 0) {
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+ res = error_errno(_("could not duplicate stdout"));
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+ goto diagnose_cleanup;
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+ }
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+
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+ archiver_fd = xopen(zip_path.buf, O_CREAT | O_WRONLY | O_TRUNC, 0666);
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+ if (archiver_fd < 0 || dup2(archiver_fd, 1) < 0) {
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+ res = error_errno(_("could not redirect output"));
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+ goto diagnose_cleanup;
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+ }
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+
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+ init_zip_archiver();
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+ strvec_pushl(&archiver_args, "scalar-diagnose", "--format=zip", NULL);
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+
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+ strbuf_reset(&buf);
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+ strbuf_addstr(&buf, "Collecting diagnostic info\n\n");
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+ get_version_info(&buf, 1);
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+
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+ strbuf_addf(&buf, "Enlistment root: %s\n", the_repository->worktree);
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+ write_or_die(stdout_fd, buf.buf, buf.len);
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+ strvec_pushf(&archiver_args,
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+ "--add-virtual-file=diagnostics.log:%.*s",
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+ (int)buf.len, buf.buf);
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+
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+ if ((res = add_directory_to_archiver(&archiver_args, ".git", 0)) ||
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+ (res = add_directory_to_archiver(&archiver_args, ".git/hooks", 0)) ||
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+ (res = add_directory_to_archiver(&archiver_args, ".git/info", 0)) ||
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+ (res = add_directory_to_archiver(&archiver_args, ".git/logs", 1)) ||
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+ (res = add_directory_to_archiver(&archiver_args, ".git/objects/info", 0)))
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+ goto diagnose_cleanup;
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+
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+ strvec_pushl(&archiver_args, "--prefix=",
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+ oid_to_hex(the_hash_algo->empty_tree), "--", NULL);
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+
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+ /* `write_archive()` modifies the `argv` passed to it. Let it. */
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+ argv_copy = xmemdupz(archiver_args.v,
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+ sizeof(char *) * archiver_args.nr);
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+ res = write_archive(archiver_args.nr, (const char **)argv_copy, NULL,
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+ the_repository, NULL, 0);
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+ if (res) {
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+ error(_("failed to write archive"));
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+ goto diagnose_cleanup;
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+ }
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+
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+ if (!res)
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+ fprintf(stderr, "\n"
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+ "Diagnostics complete.\n"
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+ "All of the gathered info is captured in '%s'\n",
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+ zip_path.buf);
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+
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+diagnose_cleanup:
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+ if (archiver_fd >= 0) {
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+ close(1);
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+ dup2(stdout_fd, 1);
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+ }
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+ free(argv_copy);
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+ strvec_clear(&archiver_args);
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+ strbuf_release(&zip_path);
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+ strbuf_release(&path);
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+ strbuf_release(&buf);
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+
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+ return res;
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+}
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+
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static int cmd_list(int argc, const char **argv)
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{
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if (argc != 1)
@@ -801,6 +944,7 @@ static struct {
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{ "reconfigure", cmd_reconfigure },
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{ "delete", cmd_delete },
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{ "version", cmd_version },
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+ { "diagnose", cmd_diagnose },
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{ NULL, NULL},
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};
950
contrib/scalar/scalar.txt
+12
@@ -14,6 +14,7 @@ scalar register [<enlistment>]
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scalar unregister [<enlistment>]
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scalar run ( all | config | commit-graph | fetch | loose-objects | pack-files ) [<enlistment>]
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scalar reconfigure [ --all | <enlistment> ]
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+scalar diagnose [<enlistment>]
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scalar delete <enlistment>
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DESCRIPTION
@@ -139,6 +140,17 @@ reconfigure the enlistment.
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With the `--all` option, all enlistments currently registered with Scalar
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will be reconfigured. Use this option after each Scalar upgrade.
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+Diagnose
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+~~~~~~~~
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+
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+diagnose [<enlistment>]::
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+ When reporting issues with Scalar, it is often helpful to provide the
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+ information gathered by this command, including logs and certain
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+ statistics describing the data shape of the current enlistment.
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++
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+The output of this command is a `.zip` file that is written into
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+a directory adjacent to the worktree in the `src` directory.
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+
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Delete
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~~~~~~
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contrib/scalar/t/t9099-scalar.sh
+14
@@ -98,4 +98,18 @@ test_expect_success '`scalar [...] <dir>` errors out when dir is missing' '
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grep "cloned. does not exist" err
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'
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+SQ="'"
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+test_expect_success UNZIP 'scalar diagnose' '
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+ scalar clone "file://$(pwd)" cloned --single-branch &&
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+ scalar diagnose cloned >out 2>err &&
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+ sed -n "s/.*$SQ\\(.*\\.zip\\)$SQ.*/\\1/p" <err >zip_path &&
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+ zip_path=$(cat zip_path) &&
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+ test -n "$zip_path" &&
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+ unzip -v "$zip_path" &&
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+ folder=${zip_path%.zip} &&
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+ test_path_is_missing "$folder" &&
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+ unzip -p "$zip_path" diagnostics.log >out &&
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+ test_file_not_empty out
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+'
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+
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test_done