Remove $realpath (fix #21)

Author: rrthomas

Cookbook.md

@@ -232,10 +232,10 @@ $run(make-zip.in.sh,\$outputpath/\$path)
 
 ## Processing files in the input directory
 
-Sometimes we would like to process input files using a command other than `nancy`. For example, a file can display its own modification date using `$realpath` like this:
+Sometimes we would like to process input files using a command other than `nancy`. For example, a file can display its own modification date using `NANCY_INPUT` like this:
 
 ```
-$run(date,-d,@$run(stat,-c%Y,$realpath),+%F)
+$run(date,-d,@$run(sh,-c,stat -c%Y \\$NANCY_INPUT/$path),+%F)
 ```
 
 We might want to process a different file. For example, [`timeplate.in.html`](#website-example) could display the modification date of `main.in.html` using `$filename` like this:

Cookbook.nancy.md

@@ -129,10 +129,10 @@ Assuming it is called `make-zip.in.sh`, it can be used thus, from a file called
 
 ## Processing files in the input directory
 
-Sometimes we would like to process input files using a command other than `nancy`. For example, a file can display its own modification date using `\$realpath` like this:
+Sometimes we would like to process input files using a command other than `nancy`. For example, a file can display its own modification date using `NANCY_INPUT` like this:
 
 ```
-\$run(date,-d,@$run(stat,-c%Y,$realpath),+%F)
+\$run(date,-d,@$run(sh,-c,stat -c%Y \\$NANCY_INPUT/$path),+%F)
 ```
 
 We might want to process a different file. For example, [`timeplate.in.html`](#website-example) could display the modification date of `main.in.html` using `\$filename` like this:

README.md

@@ -160,7 +160,6 @@ Nancy recognises these commands:
 + *`$path`* Expands to the file currently being expanded, relative to the
   input tree. This is always a template file, unless the current input path
   is a single file.
-+ *`$realpath`* Returns the real path of the file currently being expanded.
 + *`$outputpath`* Returns the path of the output tree for the file currently
   being expanded, relative to `NANCY_OUTPUT`.
 
@@ -210,18 +209,17 @@ See the [date example](Cookbook.md#date-example) in the Cookbook for more
 detail.
 
 If one command is nested inside another, the inner command will be processed
-first. This means that if, for example, `$realpath` is passed as an
-argument to a program, the program will be given the actual path, rather
-than the string `$realpath`. Arguments and command inputs are processed
-from left to right.
+first. This means that if, for example, `$path` is passed as an argument to
+a program, the program will be given the actual path, rather than the string
+`$path`. Arguments and command inputs are processed from left to right.
 
 ### Environment variables provided by `$run`
 
 When Nancy `$run`s a program, it sets the following environment variables:
 
-- NANCY_INPUT - the root of whichever of the input trees contains the file that
-  is being expanded: a prefix of `$realpath`. The file's name, relative to
-  `NANCY_INPUT`, is `$path`.
+- NANCY_INPUT - the root of whichever of the input trees contains the file
+  that is being expanded. The file's name, relative to `NANCY_INPUT`, is
+  `$path`.
 - NANCY_OUTPUT - the root of the output tree.
 
 ### Escaping

README.nancy.md

@@ -143,7 +143,6 @@ Nancy recognises these commands:
 + *`\$path`* Expands to the file currently being expanded, relative to the
   input tree. This is always a template file, unless the current input path
   is a single file.
-+ *`\$realpath`* Returns the real path of the file currently being expanded.
 + *`\$outputpath`* Returns the path of the output tree for the file currently
   being expanded, relative to `NANCY_OUTPUT`.
 
@@ -193,18 +192,17 @@ See the [date example](Cookbook.md#date-example) in the Cookbook for more
 detail.
 
 If one command is nested inside another, the inner command will be processed
-first. This means that if, for example, `\$realpath` is passed as an
-argument to a program, the program will be given the actual path, rather
-than the string `\$realpath`. Arguments and command inputs are processed
-from left to right.
+first. This means that if, for example, `\$path` is passed as an argument to
+a program, the program will be given the actual path, rather than the string
+`\$path`. Arguments and command inputs are processed from left to right.
 
 ### Environment variables provided by `\$run`
 
 When Nancy `\$run`s a program, it sets the following environment variables:
 
-- NANCY_INPUT - the root of whichever of the input trees contains the file that
-  is being expanded: a prefix of `\$realpath`. The file's name, relative to
-  `NANCY_INPUT`, is `\$path`.
+- NANCY_INPUT - the root of whichever of the input trees contains the file
+  that is being expanded. The file's name, relative to `NANCY_INPUT`, is
+  `\$path`.
 - NANCY_OUTPUT - the root of the output tree.
 
 ### Escaping

nancy/__init__.py

@@ -266,7 +266,7 @@ def __init__(
     def input_file(self):
         """Returns the filesystem input `Path`."""
         if self.root is None:
-            raise ValueError("$realpath is not available for directories")
+            raise ValueError("input_file() is not available for directories")
         return self.root / self.path
 
     def output_path(self):
@@ -453,13 +453,6 @@ def path(self, args: Optional[list[bytes]], input: Optional[bytes]) -> bytes:
             raise ValueError("$path does not take an input")
         return bytes(self._expand.path)
 
-    def realpath(self, args: Optional[list[bytes]], input: Optional[bytes]) -> bytes:
-        if args is not None:
-            raise ValueError("$realpath does not take arguments")
-        if input is not None:
-            raise ValueError("$realpath does not take an input")
-        return bytes(self._expand.input_file())
-
     def outputpath(self, args: Optional[list[bytes]], input: Optional[bytes]) -> bytes:
         if args is not None:
             raise ValueError("$outputpath does not take arguments")