Fix default template when details are missing

src/README.j2

@@ -1,20 +1,20 @@
 {# this is the default template used when the user does not specify one #}
 
-{%- if crate is defined -%}
+{%- if crate -%}
 # {{ crate }}
-	{%- if license is defined %} ![License: {{ license }}](https://img.shields.io/badge/license-{{ license | replace("-", "--") | urlencode }}-blue)
+	{%- if license %} ![License: {{ license }}](https://img.shields.io/badge/license-{{ license | replace("-", "--") | urlencode }}-blue)
 	{%- else %} ![License](https://img.shields.io/crates/l/{{ crate | urlencode }})
 	{%- endif %}
-	{%- if crate is defined %} [![{{ crate }} on crates.io](https://img.shields.io/crates/v/{{ crate | urlencode }})](https://crates.io/crates/{{ crate | urlencode }})
+	{%- if crate %} [![{{ crate }} on crates.io](https://img.shields.io/crates/v/{{ crate | urlencode }})](https://crates.io/crates/{{ crate | urlencode }})
 		{%- if target == "lib" %} [![{{ crate }} on docs.rs](https://docs.rs/{{ crate | urlencode }}/badge.svg)](https://docs.rs/{{ crate | urlencode }})
 		{%- endif %}
 	{%- endif %}
-	{%- if repository is defined %}
+	{%- if repository %}
 		{%- if repository_host == "github.com" %} [![Source Code Repository](https://img.shields.io/badge/Code-On%20GitHub-blue?logo=GitHub)]({{ repository }})
-		{%- elif repository_host is defined %} [![Source Code Repository](https://img.shields.io/badge/Code-On%20{{ repository_host | replace("-", "--") | urlencode }}-blue)]({{ repository }})
+		{%- elif repository_host %} [![Source Code Repository](https://img.shields.io/badge/Code-On%20{{ repository_host | replace("-", "--") | urlencode }}-blue)]({{ repository }})
 		{%- endif %}
 	{%- endif %}
-	{%- if rust_version is defined %} ![Rust Version: {{rust_version}}](https://img.shields.io/badge/rustc-{{ rust_version | urlencode }}-orange.svg)
+	{%- if rust_version %} ![Rust Version: {{rust_version}}](https://img.shields.io/badge/rustc-{{ rust_version | urlencode }}-orange.svg)
 	{%- endif %}
 {%- endif %}
 

tests/pass/default-template-no-details/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "default_template_no_details"
+version = "0.0.0"
+publish = false
+edition = "2021"
+
+[lib]
+path = "lib.rs"

tests/pass/default-template-no-details/README.md

@@ -0,0 +1,4 @@
+# default_template_no_details ![License](https://img.shields.io/crates/l/default_template_no_details) [![default_template_no_details on crates.io](https://img.shields.io/crates/v/default_template_no_details)](https://crates.io/crates/default_template_no_details) [![default_template_no_details on docs.rs](https://docs.rs/default_template_no_details/badge.svg)](https://docs.rs/default_template_no_details)
+
+This test ensures that the default template behaves well when there are no details (like description, license, rust-version etc) defined in the `Cargo.toml` file.
+

tests/pass/default-template-no-details/lib.rs

@@ -0,0 +1,2 @@
+//! This test ensures that the default template behaves well when there are no details
+//! (like description, license, rust-version etc) defined in the `Cargo.toml` file.