style: Clarification of decode information types for PNG, PNM and PVR…

… formats
yegor-pelykh · May 17, 2024 · e80c656 · e80c656
1 parent a672ccf
commit e80c656
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Showing 3 changed files with 20 additions and 14 deletions.
diff --git a/src/formats/png-decoder.ts b/src/formats/png-decoder.ts
@@ -435,7 +435,7 @@ export class PngDecoder implements Decoder {
    * Start decoding the data as an animation sequence, but don't actually
    * process the frames until they are requested with decodeFrame.
    */
-  public startDecode(bytes: Uint8Array): DecodeInfo | undefined {
+  public startDecode(bytes: Uint8Array): PngInfo | undefined {
     if (!this.isValidFile(bytes) || this._input === undefined) {
       return undefined;
     }

diff --git a/src/formats/pnm-decoder.ts b/src/formats/pnm-decoder.ts
@@ -103,7 +103,7 @@ export class PnmDecoder implements Decoder {
     );
   }
 
-  public startDecode(bytes: Uint8Array): DecodeInfo | undefined {
+  public startDecode(bytes: Uint8Array): PnmInfo | undefined {
     this._input = new InputBuffer({
       buffer: bytes,
     });

diff --git a/src/formats/pvr-decoder.ts b/src/formats/pvr-decoder.ts
@@ -29,7 +29,7 @@ export class PvrDecoder implements Decoder {
     return 1;
   }
 
-  private decodePvr3Header(bytes: Uint8Array): DecodeInfo | undefined {
+  private decodePvr3Header(bytes: Uint8Array): Pvr3Info | undefined {
     const input = new InputBuffer({
       buffer: bytes,
     });
@@ -76,7 +76,7 @@ export class PvrDecoder implements Decoder {
     return info;
   }
 
-  private decodePvr2Header(bytes: Uint8Array): DecodeInfo | undefined {
+  private decodePvr2Header(bytes: Uint8Array): Pvr2Info | undefined {
     const input = new InputBuffer({
       buffer: bytes,
     });
@@ -122,7 +122,7 @@ export class PvrDecoder implements Decoder {
     return info;
   }
 
-  private decodeApplePvrtcHeader(bytes: Uint8Array): DecodeInfo | undefined {
+  private decodeApplePvrtcHeader(bytes: Uint8Array): PvrAppleInfo | undefined {
     const fileSize = bytes.length;
 
     const input = new InputBuffer({
@@ -737,7 +737,9 @@ export class PvrDecoder implements Decoder {
     return this.startDecode(bytes) !== undefined;
   }
 
-  public startDecode(bytes: Uint8Array): DecodeInfo | undefined {
+  public startDecode(
+    bytes: Uint8Array
+  ): PvrAppleInfo | Pvr3Info | Pvr2Info | undefined {
     // Use a heuristic to detect potential apple PVRTC formats
     if (this.countBits(bytes.length) === 1) {
       // very likely to be apple PVRTC
@@ -748,16 +750,20 @@ export class PvrDecoder implements Decoder {
       }
     }
 
-    let info = this.decodePvr3Header(bytes);
-    if (info !== undefined) {
-      this._data = bytes;
-      return (this._info = info);
+    {
+      const info = this.decodePvr3Header(bytes);
+      if (info !== undefined) {
+        this._data = bytes;
+        return (this._info = info);
+      }
     }
 
-    info = this.decodePvr2Header(bytes);
-    if (info !== undefined) {
-      this._data = bytes;
-      return (this._info = info);
+    {
+      const info = this.decodePvr2Header(bytes);
+      if (info !== undefined) {
+        this._data = bytes;
+        return (this._info = info);
+      }
     }
 
     return undefined;