diff --git a/apps/effectcraft-cli/src/template.rs b/apps/effectcraft-cli/src/template.rs index f4da23cd9..f84303dd0 100644 --- a/apps/effectcraft-cli/src/template.rs +++ b/apps/effectcraft-cli/src/template.rs @@ -36,7 +36,20 @@ pub(super) fn validate(cmd: &str, args: &Args) -> Result<(), Failure> { { for input in ["--template", "--values"] { if let Some(path) = args.opt(input) - && std::fs::canonicalize(path).is_ok_and(|path| path == output) + && std::fs::canonicalize(path).is_ok_and(|path| { + if path == output { + return true; + } + #[cfg(unix)] + { + use std::os::unix::fs::MetadataExt; + // Distinct canonical paths can still name the same file through hard links. + if let (Ok(input), Ok(output)) = (std::fs::metadata(&path), std::fs::metadata(&output)) { + return input.dev() == output.dev() && input.ino() == output.ino(); + } + } + false + }) { return Err(Failure::Error(format!("--out {out} would overwrite {input} {path}"))); } diff --git a/apps/effectcraft-cli/tests/qa_template.rs b/apps/effectcraft-cli/tests/qa_template.rs index ac67280ee..2765b163e 100644 --- a/apps/effectcraft-cli/tests/qa_template.rs +++ b/apps/effectcraft-cli/tests/qa_template.rs @@ -247,7 +247,7 @@ fn template_output_alias_fixture(case: &str) -> PathBuf { dir } -fn assert_template_output_preserves_inputs(dir: &PathBuf, out: &str) { +fn assert_template_output_preserves_inputs(dir: &PathBuf, out: &str) -> Value { let template_before = std::fs::read(dir.join("lt.ectemplate")).unwrap(); let values_before = std::fs::read(dir.join("values.json")).unwrap(); // Read the inputs before interpreting the subprocess status or error text. @@ -272,7 +272,8 @@ fn assert_template_output_preserves_inputs(dir: &PathBuf, out: &str) { ); assert!(template_preserved, "template rendering must preserve its template input when --out aliases that file"); assert!(values_preserved, "template rendering must preserve its values input when --out aliases that file"); - assert!(!result.status.success(), "an output alias must fail before rendering overwrites an input"); + assert_eq!(result.status.code(), Some(1), "an output alias must fail before rendering overwrites an input"); + serde_json::from_slice(&result.stdout).unwrap() } #[test] @@ -652,3 +653,39 @@ fn template_missing_output_does_not_replace_extracted_media() { assert!(media_preserved, "missing --out must fail before overwriting previously extracted media"); let _ = std::fs::remove_dir_all(&dir); } + +#[cfg(unix)] +#[test] +fn template_frame_output_cannot_alias_its_template_through_a_hard_link() { + use std::os::unix::fs::MetadataExt; + + let dir = template_output_alias_fixture("hard-linked-template"); + let input = dir.join("lt.ectemplate"); + let output = dir.join("hard-linked-template.png"); + std::fs::hard_link(&input, &output).unwrap(); + let input_metadata = std::fs::metadata(&input).unwrap(); + let output_metadata = std::fs::metadata(&output).unwrap(); + assert_eq!((input_metadata.dev(), input_metadata.ino()), (output_metadata.dev(), output_metadata.ino()), "actual hard-link file identity"); + assert_ne!(input.canonicalize().unwrap(), output.canonicalize().unwrap(), "the hard link has a distinct canonical path"); + let reply = assert_template_output_preserves_inputs(&dir, "hard-linked-template.png"); + assert_eq!(reply["error"], "--out hard-linked-template.png would overwrite --template lt.ectemplate", "{reply}"); + let _ = std::fs::remove_dir_all(&dir); +} + +#[cfg(unix)] +#[test] +fn template_frame_output_cannot_alias_its_values_through_a_hard_link() { + use std::os::unix::fs::MetadataExt; + + let dir = template_output_alias_fixture("hard-linked-values"); + let input = dir.join("values.json"); + let output = dir.join("hard-linked-values.png"); + std::fs::hard_link(&input, &output).unwrap(); + let input_metadata = std::fs::metadata(&input).unwrap(); + let output_metadata = std::fs::metadata(&output).unwrap(); + assert_eq!((input_metadata.dev(), input_metadata.ino()), (output_metadata.dev(), output_metadata.ino()), "actual hard-link file identity"); + assert_ne!(input.canonicalize().unwrap(), output.canonicalize().unwrap(), "the hard link has a distinct canonical path"); + let reply = assert_template_output_preserves_inputs(&dir, "hard-linked-values.png"); + assert_eq!(reply["error"], "--out hard-linked-values.png would overwrite --values values.json", "{reply}"); + let _ = std::fs::remove_dir_all(&dir); +}