Initial public release of Warp.

Repo-Sync-Origin: warpdotdev/warp-internal@12af1d983b

app/src/editor/view/figma_utils/is_figma_png.rs

@@ -0,0 +1,42 @@
+/// Returns `true` if `bytes` is a PNG whose `tEXt` metadata contains `Software: Figma`.
+///
+/// Figma exports PNGs with a `tEXt` chunk where the keyword is `Software` and the value
+/// is `Figma`. We scan the raw chunk stream for this marker without pulling in an image
+/// parsing library, keeping the check lightweight.
+const PNG_SIGNATURE: &[u8] = b"\x89PNG\r\n\x1a\n";
+
+pub fn is_figma_png(bytes: &[u8]) -> bool {
+    if !bytes.starts_with(PNG_SIGNATURE) {
+        return false;
+    }
+    let mut offset = 8usize;
+    while offset + 12 <= bytes.len() {
+        let length = u32::from_be_bytes([
+            bytes[offset],
+            bytes[offset + 1],
+            bytes[offset + 2],
+            bytes[offset + 3],
+        ]) as usize;
+        let type_start = offset + 4;
+        let data_start = type_start + 4;
+        let Some(data_end) = data_start.checked_add(length) else {
+            break;
+        };
+        if data_end + 4 > bytes.len() {
+            break;
+        }
+        // tEXt chunk: data is `keyword\0text`
+        if &bytes[type_start..data_start] == b"tEXt"
+            && bytes[data_start..data_end].starts_with(b"Software\x00Figma")
+        {
+            return true;
+        }
+        // Advance past: length(4) + type(4) + data(length) + CRC(4)
+        offset = data_end + 4;
+    }
+    false
+}
+
+#[cfg(test)]
+#[path = "is_figma_png_tests.rs"]
+mod tests;

app/src/editor/view/figma_utils/is_figma_png_tests.rs

@@ -0,0 +1,85 @@
+use super::is_figma_png;
+
+fn build_png_with_text_chunk(keyword: &[u8], text: &[u8]) -> Vec<u8> {
+    let mut bytes = Vec::new();
+    bytes.extend_from_slice(b"\x89PNG\r\n\x1a\n");
+    let data: Vec<u8> = keyword.iter().chain(b"\x00").chain(text).copied().collect();
+    let length = data.len() as u32;
+    bytes.extend_from_slice(&length.to_be_bytes());
+    bytes.extend_from_slice(b"tEXt");
+    bytes.extend_from_slice(&data);
+    bytes.extend_from_slice(&[0u8; 4]); // fake CRC
+    bytes
+}
+
+#[test]
+fn returns_true_for_figma_export_png() {
+    let bytes = include_bytes!("figma-export.png");
+    assert!(is_figma_png(bytes));
+}
+
+#[test]
+fn returns_false_for_non_figma_png() {
+    let bytes = include_bytes!("non-figma-export.png");
+    assert!(!is_figma_png(bytes));
+}
+
+#[test]
+fn returns_false_for_empty_bytes() {
+    assert!(!is_figma_png(&[]));
+}
+
+#[test]
+fn returns_false_for_invalid_png_signature() {
+    let mut bytes = b"\x00PNG\r\n\x1a\n".to_vec();
+    bytes.extend_from_slice(&[0u8; 12]);
+    assert!(!is_figma_png(&bytes));
+}
+
+#[test]
+fn returns_true_for_crafted_png_with_software_figma() {
+    let bytes = build_png_with_text_chunk(b"Software", b"Figma");
+    assert!(is_figma_png(&bytes));
+}
+
+#[test]
+fn returns_false_when_text_chunk_keyword_is_not_software() {
+    let bytes = build_png_with_text_chunk(b"Author", b"Figma");
+    assert!(!is_figma_png(&bytes));
+}
+
+#[test]
+fn returns_false_when_software_value_is_not_figma() {
+    let bytes = build_png_with_text_chunk(b"Software", b"Sketch");
+    assert!(!is_figma_png(&bytes));
+}
+
+#[test]
+fn returns_true_when_figma_text_chunk_follows_another_chunk() {
+    let mut bytes = Vec::new();
+    bytes.extend_from_slice(b"\x89PNG\r\n\x1a\n");
+    // A preceding chunk (e.g. tIME)
+    let preceding = b"dummy data";
+    bytes.extend_from_slice(&(preceding.len() as u32).to_be_bytes());
+    bytes.extend_from_slice(b"tIME");
+    bytes.extend_from_slice(preceding);
+    bytes.extend_from_slice(&[0u8; 4]); // fake CRC
+                                        // tEXt chunk with Software: Figma
+    let text_data = b"Software\x00Figma";
+    bytes.extend_from_slice(&(text_data.len() as u32).to_be_bytes());
+    bytes.extend_from_slice(b"tEXt");
+    bytes.extend_from_slice(text_data);
+    bytes.extend_from_slice(&[0u8; 4]); // fake CRC
+    assert!(is_figma_png(&bytes));
+}
+
+#[test]
+fn returns_false_for_truncated_chunk_data() {
+    let mut bytes = Vec::new();
+    bytes.extend_from_slice(b"\x89PNG\r\n\x1a\n");
+    // Declare length as 100 but provide fewer bytes
+    bytes.extend_from_slice(&100u32.to_be_bytes());
+    bytes.extend_from_slice(b"tEXt");
+    bytes.extend_from_slice(b"Software\x00Figma"); // only 15 bytes, not 100
+    assert!(!is_figma_png(&bytes));
+}

app/src/editor/view/figma_utils/mod.rs

@@ -0,0 +1,3 @@
+mod is_figma_png;
+
+pub use is_figma_png::is_figma_png;