events: Add builder-style methods to media event content structs

crates/ruma-common/src/events/room/message/audio.rs

@@ -42,6 +42,15 @@ impl AudioMessageEventContent {
     pub fn encrypted(body: String, file: EncryptedFile) -> Self {
         Self::new(body, MediaSource::Encrypted(Box::new(file)))
     }
+
+    /// Creates a new `AudioMessageEventContent` from `self` with the `info` field set to the given
+    /// value.
+    ///
+    /// Since the field is public, you can also assign to it directly. This method merely acts
+    /// as a shorthand for that, because it is very common to set this field.
+    pub fn info(self, info: impl Into<Option<Box<AudioInfo>>>) -> Self {
+        Self { info: info.into(), ..self }
+    }
 }
 
 /// Metadata about an audio clip.

crates/ruma-common/src/events/room/message/file.rs

@@ -46,6 +46,24 @@ impl FileMessageEventContent {
     pub fn encrypted(body: String, file: EncryptedFile) -> Self {
         Self::new(body, MediaSource::Encrypted(Box::new(file)))
     }
+
+    /// Creates a new `FileMessageEventContent` from `self` with the `filename` field set to the
+    /// given value.
+    ///
+    /// Since the field is public, you can also assign to it directly. This method merely acts
+    /// as a shorthand for that, because it is very common to set this field.
+    pub fn filename(self, filename: impl Into<Option<String>>) -> Self {
+        Self { filename: filename.into(), ..self }
+    }
+
+    /// Creates a new `FileMessageEventContent` from `self` with the `info` field set to the given
+    /// value.
+    ///
+    /// Since the field is public, you can also assign to it directly. This method merely acts
+    /// as a shorthand for that, because it is very common to set this field.
+    pub fn info(self, info: impl Into<Option<Box<FileInfo>>>) -> Self {
+        Self { info: info.into(), ..self }
+    }
 }
 
 /// Metadata about a file.

crates/ruma-common/src/events/room/message/image.rs

@@ -41,4 +41,13 @@ impl ImageMessageEventContent {
     pub fn encrypted(body: String, file: EncryptedFile) -> Self {
         Self::new(body, MediaSource::Encrypted(Box::new(file)))
     }
+
+    /// Creates a new `ImageMessageEventContent` from `self` with the `info` field set to the given
+    /// value.
+    ///
+    /// Since the field is public, you can also assign to it directly. This method merely acts
+    /// as a shorthand for that, because it is very common to set this field.
+    pub fn info(self, info: impl Into<Option<Box<ImageInfo>>>) -> Self {
+        Self { info: info.into(), ..self }
+    }
 }

crates/ruma-common/src/events/room/message/video.rs

@@ -43,6 +43,15 @@ impl VideoMessageEventContent {
     pub fn encrypted(body: String, file: EncryptedFile) -> Self {
         Self::new(body, MediaSource::Encrypted(Box::new(file)))
     }
+
+    /// Creates a new `VideoMessageEventContent` from `self` with the `info` field set to the given
+    /// value.
+    ///
+    /// Since the field is public, you can also assign to it directly. This method merely acts
+    /// as a shorthand for that, because it is very common to set this field.
+    pub fn info(self, info: impl Into<Option<Box<VideoInfo>>>) -> Self {
+        Self { info: info.into(), ..self }
+    }
 }
 
 /// Metadata about a video.