Auto merge of rust-lang#66314 - GuillaumeGomez:move-error-codes, r=Centril

Move error codes

Works towards rust-lang#66210.

r? @Centril

Oh btw, for the ones interested, I used this python script to get all error codes content sorted into one final file:

<details>

```python
from os import listdir
from os.path import isdir, isfile, join

def get_error_codes(error_codes, f_path):
    with open(f_path) as f:
        short_mode = False
        lines = f.read().split("\n")
        i = 0
        while i < len(lines):
            line = lines[i]
            if not short_mode and line.startswith("E0") and line.endswith(": r##\""):
                error = line
                error += "\n"
                i += 1
                while i < len(lines):
                    line = lines[i]
                    error += line
                    if line.endswith("\"##,"):
                        break
                    error += "\n"
                    i += 1
                error_codes["long"].append(error)
            elif line == ';':
                short_mode = True
            elif short_mode is True and len(line) > 0 and line != "}":
                error_codes["short"].append(line)
                while i + 1 < len(lines):
                    line = lines[i + 1].strip()
                    if not line.startswith("//"):
                        break
                    parts = line.split("//")
                    if len(parts) < 2:
                        break
                    if parts[1].strip().startswith("E0"):
                        break
                    error_codes["short"][-1] += "\n"
                    error_codes["short"][-1] += lines[i + 1]
                    i += 1
            i += 1

def loop_dirs(error_codes, cur_dir):
    for entry in listdir(cur_dir):
        f = join(cur_dir, entry)
        if isfile(f) and entry == "error_codes.rs":
            get_error_codes(error_codes, f)
        elif isdir(f) and not entry.startswith("librustc_error_codes"):
            loop_dirs(error_codes, f)

def get_error_code(err):
    x = err.split(",")
    if len(x) < 2:
        return err
    x = x[0]
    if x.strip().startswith("//"):
        x = x.split("//")[1].strip()
    return x.strip()

def write_into_file(error_codes, f_path):
    with open(f_path, "w") as f:
        f.write("// Error messages for EXXXX errors.  Each message should start and end with a\n")
        f.write("// new line, and be wrapped to 80 characters.  In vim you can `:set tw=80` and\n")
        f.write("// use `gq` to wrap paragraphs. Use `:set tw=0` to disable.\n\n")
        f.write("syntax::register_diagnostics! {\n\n")
        error_codes["long"].sort()
        for i in error_codes["long"]:
            f.write(i)
            f.write("\n\n")
        f.write(";\n")
        error_codes["short"] = sorted(error_codes["short"], key=lambda err: get_error_code(err))
        for i in error_codes["short"]:
            f.write(i)
            f.write("\n")
        f.write("}\n")

error_codes = {
    "long": [],
    "short": []
}
loop_dirs(error_codes, "src")
write_into_file(error_codes, "src/librustc_error_codes/src/error_codes.rs")
```
</details>

And to move the error codes into their own files:

<details>

```python
import os

try:
    os.mkdir("src/librustc_error_codes/error_codes")
except OSError:
    print("Seems like folder already exist, moving on!")
data = ''
with open("src/librustc_error_codes/error_codes.rs") as f:
    x = f.read().split('\n')
    i = 0
    short_part = False
    while i < len(x):
        line = x[i]
        if short_part is False and line.startswith('E0') and line.endswith(': r##"'):
            err_code = line.split(':')[0]
            i += 1
            content = ''
            while i < len(x):
                if x[i] == '"##,':
                    break
                content += x[i]
                content += '\n'
                i += 1
            f_path = "src/librustc_error_codes/error_codes/{}.md".format(err_code)
            with open(f_path, "w") as ff:
                ff.write(content)
            data += '{}: include_str!("./error_codes/{}.md"),'.format(err_code, err_code)
        elif short_part is False and line == ';':
            short_part is True
            data += ';\n'
        else:
            data += line
            data += '\n'
        i += 1
with open("src/librustc_error_codes/error_codes.rs", "w") as f:
    f.write(data)
```
</details>

Author: bors

Cargo.lock

@@ -3120,13 +3120,15 @@ dependencies = [
  "graphviz",
  "jobserver",
  "log",
+ "measureme",
  "num_cpus",
  "parking_lot 0.9.0",
  "polonius-engine",
  "rustc-rayon 0.3.0",
  "rustc-rayon-core 0.3.0",
  "rustc_apfloat",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_fs_util",
  "rustc_index",
@@ -3439,6 +3441,7 @@ dependencies = [
  "rustc_apfloat",
  "rustc_codegen_utils",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_fs_util",
  "rustc_incremental",
@@ -3516,6 +3519,10 @@ dependencies = [
  "syntax_pos",
 ]
 
+[[package]]
+name = "rustc_error_codes"
+version = "0.0.0"
+
 [[package]]
 name = "rustc_errors"
 version = "0.0.0"
@@ -3569,6 +3576,7 @@ dependencies = [
  "rustc_codegen_ssa",
  "rustc_codegen_utils",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_incremental",
  "rustc_lint",
@@ -3605,6 +3613,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_index",
  "rustc_target",
  "syntax",
@@ -3650,6 +3659,7 @@ dependencies = [
  "memmap",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_index",
  "rustc_parse",
@@ -3675,6 +3685,7 @@ dependencies = [
  "rustc",
  "rustc_apfloat",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_index",
  "rustc_lexer",
@@ -3703,6 +3714,7 @@ dependencies = [
  "bitflags",
  "log",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_lexer",
  "rustc_target",
@@ -3718,6 +3730,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_index",
  "rustc_parse",
@@ -3738,6 +3751,7 @@ name = "rustc_plugin_impl"
 version = "0.0.0"
 dependencies = [
  "rustc",
+ "rustc_error_codes",
  "rustc_metadata",
  "syntax",
  "syntax_expand",
@@ -3751,6 +3765,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_typeck",
  "syntax",
  "syntax_pos",
@@ -3765,6 +3780,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_metadata",
  "smallvec 1.0.0",
@@ -3844,6 +3860,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_index",
  "rustc_target",
@@ -4380,6 +4397,7 @@ dependencies = [
  "lazy_static 1.3.0",
  "log",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_index",
  "rustc_lexer",
@@ -4411,6 +4429,7 @@ dependencies = [
  "fmt_macros",
  "log",
  "rustc_data_structures",
+ "rustc_error_codes",
  "rustc_errors",
  "rustc_parse",
  "rustc_target",

src/librustc/Cargo.toml

@@ -40,3 +40,5 @@ byteorder = { version = "1.3" }
 chalk-engine = { version = "0.9.0", default-features=false }
 rustc_fs_util = { path = "../librustc_fs_util" }
 smallvec = { version = "1.0", features = ["union", "may_dangle"] }
+measureme = "0.4"
+rustc_error_codes = { path = "../librustc_error_codes" }