Inline scripts

NEWS.md

@@ -1,5 +1,10 @@
 # Development version
 
+* `rig run` now support self-contained scripts, that declare the packages
+  and the R version they need in a `# /// script` comment block. rig then
+  runs the script in its own environment, in the cache directory, and
+  installs R and the packages as needed.
+
 * `rig add` now has a `--json` option. It prints information about the
   installed R version (or the already installed version that was kept),
   including whether it is a new installation and whether it is the default.

src/args.rs

@@ -1261,6 +1261,7 @@ pub fn rig_app() -> Command {
                             "p3m",
                             "git-mirrors",
                             "url-pkgs",
+                            "scripts",
                         ]),
                 ),
         );

src/cache_cmd.rs

@@ -5,7 +5,7 @@
 //! their own corner of `real_cache_dir()`, see [`crate::cache`]. Rather than
 //! teach this module every producer's file-naming scheme, categories are
 //! derived from the *name of the top-level entry* in the cache directory:
-//! `built`, `packages`, `p3m`, `git-mirrors` and `url-pkgs` are their own
+//! `built`, `packages`, `p3m`, `git-mirrors`, `url-pkgs` and `scripts` are their own
 //! category, `metadata` collects every other kind of package metadata
 //! (binary indexes, CRAN-like databases, package manifests, repo data), and
 //! anything unrecognized left over at the cache root (e.g. stray files from
@@ -30,16 +30,18 @@ enum CacheCategory {
     P3m,
     GitMirrors,
     UrlPkgs,
+    Scripts,
 }
 
 impl CacheCategory {
-    const ALL: [CacheCategory; 6] = [
+    const ALL: [CacheCategory; 7] = [
         CacheCategory::Built,
         CacheCategory::Packages,
         CacheCategory::Metadata,
         CacheCategory::P3m,
         CacheCategory::GitMirrors,
         CacheCategory::UrlPkgs,
+        CacheCategory::Scripts,
     ];
 
     fn label(self) -> &'static str {
@@ -50,6 +52,7 @@ impl CacheCategory {
             CacheCategory::P3m => "P3M status",
             CacheCategory::GitMirrors => "Git mirrors",
             CacheCategory::UrlPkgs => "URL packages",
+            CacheCategory::Scripts => "Script environments",
         }
     }
 
@@ -63,6 +66,7 @@ impl CacheCategory {
             CacheCategory::P3m => "p3m",
             CacheCategory::GitMirrors => "git-mirrors",
             CacheCategory::UrlPkgs => "url-pkgs",
+            CacheCategory::Scripts => "scripts",
         }
     }
 }
@@ -76,6 +80,7 @@ fn classify_entry(name: &str) -> CacheCategory {
         "p3m" => CacheCategory::P3m,
         "git-mirrors" => CacheCategory::GitMirrors,
         "url-pkgs" => CacheCategory::UrlPkgs,
+        "scripts" => CacheCategory::Scripts,
         _ => CacheCategory::Metadata,
     }
 }
@@ -120,8 +125,8 @@ fn dir_usage(path: &Path) -> Usage {
     usage
 }
 
-fn cache_breakdown(cache_dir: &Path) -> [Usage; 6] {
-    let mut totals = [Usage::default(); 6];
+fn cache_breakdown(cache_dir: &Path) -> [Usage; CacheCategory::ALL.len()] {
+    let mut totals = [Usage::default(); CacheCategory::ALL.len()];
     let entries = match fs::read_dir(cache_dir) {
         Ok(entries) => entries,
         Err(_) => return totals,
@@ -180,6 +185,8 @@ struct CacheInfo {
     git_mirrors_count: u64,
     url_pkgs_size: u64,
     url_pkgs_count: u64,
+    scripts_size: u64,
+    scripts_count: u64,
     total_size: u64,
     total_count: u64,
 }
@@ -208,6 +215,8 @@ pub fn sc_cache_info(args: &ArgMatches) -> Result<(), Box<dyn Error>> {
             git_mirrors_count: totals[4].count,
             url_pkgs_size: totals[5].size,
             url_pkgs_count: totals[5].count,
+            scripts_size: totals[6].size,
+            scripts_count: totals[6].count,
             total_size: total.size,
             total_count: total.count,
         };
@@ -316,6 +325,7 @@ mod tests {
         assert_eq!(classify_entry("leftover-file"), CacheCategory::Metadata);
         assert_eq!(classify_entry("git-mirrors"), CacheCategory::GitMirrors);
         assert_eq!(classify_entry("url-pkgs"), CacheCategory::UrlPkgs);
+        assert_eq!(classify_entry("scripts"), CacheCategory::Scripts);
     }
 
     #[test]

src/data/rvenv/R.sh

@@ -8,7 +8,9 @@
 #
 # RVENV is derived from this script's own location, so the project directory
 # can be moved or checked out anywhere.
-RVENV=$(cd "$(dirname "$0")/.." && pwd)
+# `${0%/*}` instead of `dirname`, which would be one more process to start.
+case $0 in */*) RVENV=${0%/*} ;; *) RVENV=. ;; esac
+RVENV=$(cd "$RVENV/.." && pwd)
 export RVENV
 # R_LIBS is empty, so that .libPaths()[1] stays the project library, and
 # R_LIBS_SITE points at a path that cannot exist, because an empty one does

src/help/cache-clean.md

@@ -4,6 +4,7 @@ Delete cached files
 
 Deletes files from rig's cache directory. With no options, deletes the
 whole cache. Use `--category` to delete only one category of cached files
-(`built`, `packages`, `metadata`, `p3m`, `git-mirrors` or `url-pkgs`),
+(`built`, `packages`, `metadata`, `p3m`, `git-mirrors`, `url-pkgs` or
+`scripts`),
 leaving the rest in place. See [`rig cache info`](cache.qmd#rig-cache-info)
 for what each category contains.

src/help/cache-info.md

@@ -7,7 +7,8 @@ categories: packages rig built from source, downloaded package files,
 package metadata (binary package indexes, CRAN-like package databases,
 package manifests, and repository data), the cached PPM status document,
 the persistent git mirrors kept for git/GitHub dependency resolution
-(`rig proj lock`), and the downloaded archives kept for `url` dependency
-resolution.
+(`rig proj lock`), the downloaded archives kept for `url` dependency
+resolution, and the environments of scripts with inline dependencies
+(`rig run script.R`).
 
 Use `--json` for machine-readable output.

src/help/run.md

@@ -9,6 +9,7 @@ version.
 
 ```sh
 rig run                    # start R
+rig run <script.R>         # run an R script
 rig run -f <script-file>   # run an R script
 rig run -e <expression>    # evaluate an R expression
 rig run <pkg>::<script>    # run a script from a package's exec directory
@@ -52,6 +53,42 @@ the project's own environment instead of the default R version: it runs
 Use `--no-project` to ignore a project, or `--r-version` to select an R
 version directly.
 
+## Scripts with inline dependencies
+
+`rig run -f script.R` runs an R script (the `-f` can be omitted). A
+script can declare the packages and the R version it needs in a comment
+block at its top, so it runs anywhere without a project:
+
+```r
+# /// script
+# [dependencies]
+# R = ">= 4.4"
+# cli = "*"
+# dplyr = ">= 1.1"
+#
+# [tool.rig]
+# exclude-newer = "2026-06-01"
+# ///
+library(dplyr)
+```
+
+The block starts with a `# /// script` line and ends with a `# ///` line.
+In between, every line is a comment, and without the leading `#` they form
+a TOML document. The block takes the `[dependencies]`, `[[repository]]` and
+`[tool.rig]` tables of `rproj.toml`, with the same meaning.
+
+rig creates an environment for the script in its cache directory, and runs
+the script there, isolated from your own package library. It picks an
+installed R version that fits the `R` requirement, or installs one, then
+locks and installs the packages, the same way `rig proj sync` does for a
+project. Later runs reuse the environment. Scripts with the same block
+share one environment, and changing the block creates a new one. A script
+with a block always uses its own environment, even inside a project.
+`--r-version` selects the R version, which must fit the `R` requirement.
+
+`rig cache clean --category scripts` deletes all script environments. A
+script can start with `#!/usr/bin/env -S rig run`, to run it directly.
+
 ## Project scripts
 
 A project can give its own scripts a name, in the `[[bin]]` tables of its
@@ -93,6 +130,6 @@ library and repositories too, not just its version.
 Unlike `R -e`/`R -f`, `Rscript` never echoes back the code it runs, which
 fits scripts and pipelines better than `R`'s interactive-style echo.
 
-`--rscript` works with `-e`/`-f`, project scripts, apps and `--activate`,
+`--rscript` works with `-e`/`-f`, scripts, project scripts, apps and `--activate`,
 but not with `--cmd` (`R CMD` only exists as part of the `R` front-end) or
 `--shell` (which never runs the R binary at all).

src/main.rs

@@ -12,7 +12,9 @@ use tabular::*;
 mod args;
 use args::*;
 
+mod script_meta;
 mod scrun;
+mod stdout_redirect;
 use scrun::*;
 
 #[cfg(target_os = "macos")]