Use Error & ErrorKind pair instead of simple enums

Each plugin should define its own errors with a respective variant
in the main ErrorKind of frippy.
A new procedural macro was added to reduce the boilerplate required
for new error system.
It can be used by deriving "Error" and adding a name for the Error
via the "error" attribute.

So far non of the plugins except for Url and Factoids
use their own errors yet.

1 files changed, 38 insertions, 2 deletions

diff --git a/Cargo.lock b/Cargo.lock
index dcbaad5..acb6f80 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -414,8 +414,9 @@ dependencies = [
 name = "frippy_derive"
 version = "0.1.0"
 dependencies = [
- "quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.12.13 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -926,6 +927,14 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "proc-macro2"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "pulldown-cmark"
 version = "0.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -950,6 +959,14 @@ version = "0.3.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "quote"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "r2d2"
 version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1247,6 +1264,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "syn"
+version = "0.12.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "synom"
 version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1428,6 +1455,11 @@ version = "0.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "unicode-xid"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "unicode_names"
 version = "0.1.7"
 source = "git+https://github.com/Jokler/unicode_names?branch=update-to-latest-unicode#d97b80c3c35b9f1d04085409087ef113c94cde17"
@@ -1636,10 +1668,12 @@ dependencies = [
 "checksum phf_shared 0.7.21 (registry+https://github.com/rust-lang/crates.io-index)" = "07e24b0ca9643bdecd0632f2b3da6b1b89bbb0030e0b992afc1113b23a7bc2f2"
 "checksum pkg-config 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "3a8b4c6b8165cd1a1cd4b9b120978131389f64bdaf456435caa41e630edba903"
 "checksum precomputed-hash 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
+"checksum proc-macro2 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "cd07deb3c6d1d9ff827999c7f9b04cdfd66b1b17ae508e14fe47b620f2282ae0"
 "checksum pulldown-cmark 0.0.15 (registry+https://github.com/rust-lang/crates.io-index)" = "378e941dbd392c101f2cb88097fa4d7167bc421d4b88de3ff7dbee503bc3233b"
 "checksum quick-error 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eda5fe9b71976e62bc81b781206aaa076401769b2143379d3eb2118388babac4"
 "checksum quine-mc_cluskey 0.2.4 (registry+https://github.com/rust-lang/crates.io-index)" = "07589615d719a60c8dd8a4622e7946465dfef20d1a428f969e3443e7386d5f45"
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
+"checksum quote 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1eca14c727ad12702eb4b6bfb5a232287dcf8385cb8ca83a3eeaf6519c44c408"
 "checksum r2d2 0.8.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f9078ca6a8a5568ed142083bb2f7dc9295b69d16f867ddcc9849e51b17d8db46"
 "checksum r2d2-diesel 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "eb9c29bad92da76d02bc2c020452ebc3a3fe6fa74cfab91e711c43116e4fb1a3"
 "checksum rand 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)" = "15a732abf9d20f0ad8eeb6f909bf6868722d9a06e1e50802b6a70351f40b4eb1"
@@ -1675,6 +1709,7 @@ dependencies = [
 "checksum string_cache_codegen 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "479cde50c3539481f33906a387f2bd17c8e87cb848c35b6021d41fb81ff9b4d7"
 "checksum string_cache_shared 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b1884d1bc09741d466d9b14e6d37ac89d6909cbcac41dd9ae982d4d063bbedfc"
 "checksum syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)" = "d3b891b9015c88c576343b9b3e41c2c11a51c219ef067b264bd9c8aa9b441dad"
+"checksum syn 0.12.13 (registry+https://github.com/rust-lang/crates.io-index)" = "517f6da31bc53bf080b9a77b29fbd0ff8da2f5a2ebd24c73c2238274a94ac7cb"
 "checksum synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a393066ed9010ebaed60b9eafa373d4b1baac186dd7e008555b0f702b51945b6"
 "checksum synstructure 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3a761d12e6d8dcb4dcf952a7a89b475e3a9d69e4a69307e01a470977642914bd"
 "checksum take 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b157868d8ac1f56b64604539990685fa7611d8fa9e5476cf0c02cf34d32917c5"
@@ -1695,6 +1730,7 @@ dependencies = [
 "checksum unicode-bidi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "49f2bd0c6468a8230e1db229cff8029217cf623c767ea5d60bfbd42729ea54d5"
 "checksum unicode-normalization 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "51ccda9ef9efa3f7ef5d91e8f9b83bbe6955f9bf86aec89d5cce2c874625920f"
 "checksum unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "8c1f860d7d29cf02cb2f3f359fd35991af3d30bac52c57d265a3c461074cb4dc"
+"checksum unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
 "checksum unicode_names 0.1.7 (git+https://github.com/Jokler/unicode_names?branch=update-to-latest-unicode)" = "<none>"
 "checksum unreachable 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "1f2ae5ddb18e1c92664717616dd9549dde73f539f01bd7b77c2edb2446bdff91"
 "checksum unreachable 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "382810877fe448991dfc7f0dd6e3ae5d58088fd0ea5e35189655f84e6814fa56"