From af94ad50b662819f057113065aab2ca2dd0288b2 Mon Sep 17 00:00:00 2001
From: KAMADA Ken'ichi <kamada@nanohz.org>
Date: Sat, 1 Feb 2020 20:28:21 +0900
Subject: [PATCH] Use ? instead of .unwrap() in doctests.

---
 src/lib.rs    |  6 ++++--
 src/reader.rs | 22 +++++++++++++++++-----
 src/tiff.rs   |  4 +++-
 src/writer.rs |  4 +++-
 4 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index bf1e949..eb70e80 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -35,16 +35,18 @@
 //! An example to parse JPEG/TIFF files:
 //!
 //! ```
+//! # fn main() -> Result<(), Box<dyn std::error::Error>> {
 //! for path in &["tests/exif.jpg", "tests/exif.tif"] {
-//!     let file = std::fs::File::open(path).unwrap();
+//!     let file = std::fs::File::open(path)?;
 //!     let mut bufreader = std::io::BufReader::new(&file);
 //!     let exifreader = exif::Reader::new();
-//!     let exif = exifreader.read_from_container(&mut bufreader).unwrap();
+//!     let exif = exifreader.read_from_container(&mut bufreader)?;
 //!     for f in exif.fields() {
 //!         println!("{} {} {}",
 //!                  f.tag, f.ifd_num, f.display_value().with_unit(&exif));
 //!     }
 //! }
+//! # Ok(()) }
 //! ```
 //!
 //! # Upgrade Guide from 0.4.x to 0.5.x
diff --git a/src/reader.rs b/src/reader.rs
index 45249dc..e84a686 100644
--- a/src/reader.rs
+++ b/src/reader.rs
@@ -40,13 +40,22 @@ use crate::tiff::{Field, IfdEntry, In, ProvideUnit};
 ///
 /// # Examples
 /// ```
+/// # use std::fmt::{Display, Formatter, Result};
+/// # #[derive(Debug)] struct Error(&'static str);
+/// # impl std::error::Error for Error {}
+/// # impl Display for Error {
+/// #     fn fmt(&self, f: &mut Formatter) -> Result { f.write_str(self.0) }
+/// # }
+/// # fn main() -> std::result::Result<(), Box<dyn std::error::Error>> {
 /// use exif::{In, Reader, Tag};
-/// let file = std::fs::File::open("tests/exif.jpg").unwrap();
-/// let exif = Reader::new().read_from_container(
-///     &mut std::io::BufReader::new(&file)).unwrap();
-/// let xres = exif.get_field(Tag::XResolution, In::PRIMARY).unwrap();
+/// let file = std::fs::File::open("tests/exif.jpg")?;
+/// let exif = Reader::new()
+///     .read_from_container(&mut std::io::BufReader::new(&file))?;
+/// let xres = exif.get_field(Tag::XResolution, In::PRIMARY)
+///     .ok_or(Error("tests/exif.jpg must have XResolution"))?;
 /// assert_eq!(xres.display_value().with_unit(&exif).to_string(),
 ///            "72 pixels per inch");
+/// # Ok(()) }
 /// ```
 pub struct Reader {
 }
@@ -115,18 +124,21 @@ impl Reader {
 ///
 /// # Examples
 /// ```
+/// # fn main() { sub(); }
+/// # fn sub() -> Option<()> {
 /// # use exif::{In, Reader, Tag};
 /// # let file = std::fs::File::open("tests/exif.jpg").unwrap();
 /// # let exif = Reader::new().read_from_container(
 /// #     &mut std::io::BufReader::new(&file)).unwrap();
 /// // Get a specific field.
-/// let xres = exif.get_field(Tag::XResolution, In::PRIMARY).unwrap();
+/// let xres = exif.get_field(Tag::XResolution, In::PRIMARY)?;
 /// assert_eq!(xres.display_value().with_unit(&exif).to_string(),
 ///            "72 pixels per inch");
 /// // Iterate over all fields.
 /// for f in exif.fields() {
 ///     println!("{} {} {}", f.tag, f.ifd_num, f.display_value());
 /// }
+/// # Some(()) }
 /// ```
 pub struct Exif {
     // TIFF data.
diff --git a/src/tiff.rs b/src/tiff.rs
index 166280c..46ea9f6 100644
--- a/src/tiff.rs
+++ b/src/tiff.rs
@@ -273,10 +273,12 @@ pub fn is_tiff(buf: &[u8]) -> bool {
 ///
 /// # Examples
 /// ```
+/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
 /// use exif::DateTime;
-/// let dt = DateTime::from_ascii(b"2016:05:04 03:02:01").unwrap();
+/// let dt = DateTime::from_ascii(b"2016:05:04 03:02:01")?;
 /// assert_eq!(dt.year, 2016);
 /// assert_eq!(dt.to_string(), "2016-05-04 03:02:01");
+/// # Ok(()) }
 /// ```
 #[derive(Debug)]
 pub struct DateTime {
diff --git a/src/writer.rs b/src/writer.rs
index 0270fe1..170a28a 100644
--- a/src/writer.rs
+++ b/src/writer.rs
@@ -38,6 +38,7 @@ use crate::value::Value;
 /// # Examples
 ///
 /// ```
+/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
 /// use exif::{Field, In, Tag, Value};
 /// use exif::experimental::Writer;
 /// let image_desc = Field {
@@ -48,13 +49,14 @@ use crate::value::Value;
 /// let mut writer = Writer::new();
 /// let mut buf = std::io::Cursor::new(Vec::new());
 /// writer.push_field(&image_desc);
-/// writer.write(&mut buf, false).unwrap();
+/// writer.write(&mut buf, false)?;
 /// static expected: &[u8] =
 ///     b"\x4d\x4d\x00\x2a\x00\x00\x00\x08\
 ///       \x00\x01\x01\x0e\x00\x02\x00\x00\x00\x07\x00\x00\x00\x1a\
 ///       \x00\x00\x00\x00\
 ///       Sample\0";
 /// assert_eq!(buf.into_inner(), expected);
+/// # Ok(()) }
 /// ```
 #[derive(Debug)]
 pub struct Writer<'a> {